organic garden

What’s Eating My Swiss Chard?

23 September, 2019 by amygwh

Of all the greens I like to grow in summer, Swiss chard is usually the one that is most trouble-free. It doesn’t get bitter or tough in the summer heat. It produces leaves for months on end, without sending up a flower stalk that triggers an end to leaf-production. The crop also, usually, attracts very few pests. However, this summer, something started eating my Swiss chard.

Damage in the Swiss chard patch

Holes in Swiss chard leaf, characteristic of caterpillar feeding damage

When I first noticed the damage to the Swiss chard, I figured it was caterpillars because of the kind of damage I saw on the leaves. There were big holes in the leafy parts, but the thick middle stem, or midrib, was undamaged for every leaf.

However, when I examined my patch of Swiss chard, I did not find any caterpillars, even though I found plenty of frass (caterpillar poo). I looked under the leaves, down the stems, and around the bases of the plants in my search.

University of Minnesota Extension offers several possibilities for which pests might be eating my Swiss chard, but I did not find any of the named pests. The list includes cabbage loopers, slugs (which also make holes in leaves as they eat), diamond back moths, flea beetles (which make smaller holes), and cabbage worms.

Dark wad of caterpillar frass (poo) on edge of damaged Swiss chard leaf. — Dark wad of frass on damaged leaf.

Some caterpillars are harder to find than others, so I sprayed all the chard plants with Bt for caterpillars (Thuricide, organic-approved) and figured that would stop the problem.

It didn’t. When I rechecked the patch a couple of days later, some leaves had been stripped completely down to the midribs. Caterpillars were still feasting on my plants. Since I didn’t find any caterpillars in the daytime, I changed the plan.

That night, before heading to bed, I went out to my chard patch with a flashlight and a tub that contained soapy water, prepared for a hunt.

I found caterpillars.

Caterpillars at night

That night, I found seven caterpillars on the Swiss chard, and I dropped them all into the soapy water. The caterpillars were on the Swiss chard variety ‘Perpetual spinach’, which is my favorite. The variety ‘Verde de taglio’, which has less tender leaves, also had some damage, but I did not find caterpillars on that variety.

The two groups of caterpillars most often identified as night-feeders are armyworms and cutworms.

Cutworm caterpillars

I think of cutworms as those little lumberjacks that cut down garden seedlings in the night. It didn’t occur to me that cutworms might eat bigger leaves until I saw an article about the winter cutworm, Noctua pronuba, at AskExtension.

The winter cutworm is found all across the U.S. The AskExtension article notes that the winter cutworm can be controlled with Bt for caterpillars, which is what I use on caterpillar pests, but only when the caterpillars are small. The caterpillars I found were large enough that, if they had been winter cutworms, they would have been unaffected by the Bt/Thuricide.

However, my caterpillars do not look like winter cutworms.

Armyworm caterpillars

One of the caterpillars that is eating my Swiss chard

A couple of nights after the big hunt, I went back out with the flashlight to hunt again, because leaves of my Swiss chard were still being eaten.

I found a couple more caterpillars, this time on both varieties of Swiss chard. To get a better look, I brought one of the little pests inside before drowning it in soapy water. I am pretty sure the caterpillar is an armyworm, possibly a yellow striped armyworm.

When the armyworms are as big as this — longer than an inch — handpicking and drowning the caterpillars may be the best organic option for stopping the damage in a small garden. As with the cutworms, larger caterpillars are not killed by the organic-approved Bt.

Worse, it sounds like (from reading multiple articles), a particular form of Bt is needed to get rid of the armyworms. My Thuricide won’t work on these pests. The special variation is in a product called XenTari BT. This is still an organic-approved Bt, but the strain of bacteria used to produce it is slightly different.

When I checked the product page for XenTari on amazon.com, it says the product is currently unavailable. I am guessing that is because armyworms are causing problems in more gardens than just mine, here in September.

Luckily, the batteries in my flashlight are still good. If the damage continues, I will just keep on hunting through the Swiss chard at night, until I’ve removed all of the pests.

Cucumber Bonanza Nearing its End

2 October, 2018 by amygwh

My late-planted home garden cucumbers have been coming into the kitchen for three weeks now. The fridge contains a small pile of them, and I harvested more today, but the cucumber bonanza is nearing its end. The older cucumber leaves have spots/lesions that look like downy mildew; the leaves that still are unspotted and beautifully green droop in the afternoon sun. The droop makes me think that the plants have another disease, in addition to the mildew.

Cucumber plants, wilted in the afternoon sun, but they look fine in the morning and evening, if you ignore the spotted/mildewed older leaves.

There is a bacterial wilt disease for cucumbers that is carried by cucumber beetles. I have checked the plants — leaves, stems, and flowers — very closely, and I have not seen these beetles. I have seen several bumblebees, some brown skipper-type butterflies, a few flea beetles, tiny snails, ants, a tiny native bee, a jumping spider, and one squash beetle on the plants, but those critters are not known to carry the bacterial wilt disease.

It is possible that cucumber beetles are very good at hiding. When I finally pull up the plants, I will check the stems for the white stringy goo that is a sign of bacterial wilt (as seen on the Missouri Botanical Garden page on bacterial wilt).

Cucumbers and peppers from small home garden, in October. — Today’s harvest of cucumbers and peppers.

Meanwhile, I have a small basketful of cucumbers in my kitchen. Some of them will be peeled before we eat them, because something else has scraped the outer part of the skins. If I had found cucumber beetles, I would have suspected that they caused the damage. Since I haven’t seen those beetles, and since squash beetle damage looks different (remember the semicircular troughs?), tiny snails are my current top suspects.

It is hard to say whether the cucumber part of my late-summer-garden-experiment is a bust. The harvest seems short (three+ weeks), but we have a lot of cucumbers. The zucchini part is definitely a bust. There is zero chance of getting zucchini from the sad plants in the half-barrel garden.

Of course, the pepper plants continue to grow and make peppers, unmarred by disease. Some stink bugs have found them and blemished the skins a bit, but the peppers are all still good enough. The late-planted basil will be big enough for pesto soon. Chicory is looking good, too, and so are the carrots and assorted radishes.

I will transplant the rest of my cool-season seedlings into the garden this week. Currently, they are in a flat, where I planted them in late August. The new crops are kale, spinach, beets, cilantro, and lettuce. Those will all provide food for our kitchen in the cooler months ahead.

Trap Crops for the Home Garden

28 September, 2018 by amygwh

Since trap crops take up some space, it never occurred to me that using these was a suitable organic pest control strategy for small home gardens. However, I have unexpectedly gained experience with a trap crop, since that is what my zucchini have turned out to be.

What is a trap crop?

A trap crop is one that is planted as a lure to pest insects, to keep them away from the main crop. Most trap crops are not expected to yield a harvest; instead, they are offered up to pests as an alternative to the main crop of a farm. According to SARE, trap crops are often planted around the edge of the main crop, forming a protective barrier that pests are likely to stay within. Trap crops can also be planted as a block or patch near the main crop.

According to University of Georgia, trap crops to work best when they make flowers before the main crop that they are protecting. When the plants are making flowers and fruits, that is when they are most attractive to most pests.

My zucchini plants function as a trap crop

You may have read the two recent blog posts about pests on my zucchini plants — one about squash beetles and the other about cucumber pickleworms. The squash beetles are really less of a problem, since there are only four or five each day for me to smash and the damage is limited to holes in the leaves. The pickleworms, though, are another story.

They have caused serious damage to the zucchini plants, ruining flowers and boring into main-stems and leaf-stems. The plants are still standing, but all hope of harvesting zucchini from this late-summer crop is gone.

This is the good news: my cucumber patch, planted in early August like the zucchini, has supplied several cucumbers for our meals already. Checking the cucumber plants nearly every day, I have found only a few squash beetles, grand-total, on the plants. It has been easy to find and smash the one-every-few-days beetles as I check on the garden.

In an instance of amazing good luck, my zucchini variety was so fast to mature that the plants made flowers more than a week before the cucumbers did. When the pests first showed up in my garden, the squash beetles and cucumber pickleworm moths flew past the cucumber patch, which didn’t have flowers, and attacked the zucchini plants in the half-barrel planter, where flowers and little squashes were abundant.

Cucumber patch protected by trap crop of zucchini, example of organic pest control. Zucchini are in a half-barrel at left end of garden (not in this image). — My cucumber patch in late September. No leaf mildew diseases, no pickleworm damage. PHOTO/Amygwh

Even better, the cucumbers still do not show any pickleworm damage.

To combat any pickleworms that could be present, I have been treating both sets of plants with Bt for caterpillars (the one I am using is Thuricide), which is an organic pest control product. We have had a lot of rain, though, which washes the Bt away. I am not re-spraying my plants after every rain, so some days the cucumber crop is unprotected other than by the stronger allure of the zucchini plants.

At this point, the three remaining zucchini plants look hopelessly ragged, but they are still alive. I am leaving them in the garden for as long as they continue to work as pest-magnets.

The cucumbers remain pickleworm-free, but they are not perfect specimens. I had forgotten about the uneven pollination in hot weather that results in lumpy cucumbers. These are not headed for a pickle jar, which means the imperfect shapes are not really a problem.

Weird shapes from incomplete pollination, but no cucumber pickleworm damage. PHOTO/Amygwh

Because of pest-concerns, I am harvesting the cucumbers while they are fairly small. This is a bit like harvesting tomatoes before they are fully red. I know that if I leave tomatoes in the garden to fully ripen, some pest (stink bug, chipmunk, mockingbird, etc) will notice the beautiful, ripe fruit and take a bite before I get a chance to enjoy the harvest, myself.

Unlike for tomatoes, there is not a flavor-reason to wait for more mature cucumbers. They taste pretty much the same at smaller sizes, and leaving them out in the pest-filled world seems a little like tempting fate.

So, as I ponder my next year’s garden, it is good to know that zucchini plants can use some unseen come-hither chemistry to draw pests away from the cucumbers.

This is the kind of garden-discovery that any of us can make. I have been growing food in this yard for more than 25 years, and I learn more about gardening every year. And even though there are pests, the garden is producing good food. This is part of the joy of gardening!

Are Ladybugs Eating My Squash Plants?

5 September, 2018 by amygwh

The little orange, dotted beetles that are eating my squash plants actually are in the ladybug family. Most beetles in the ladybug family do not eat plants; instead, they eat pests like aphids and whiteflies and are great helpers in our gardens. Mexican bean beetles and squash beetles, which look a lot alike, are exceptions. They are garden pests.

Right now, it is squash beetles in my garden, eating my squash plants.

It may look like ladybugs are eating my squash plants, but it is really squash beetles doing the damage.

How to identify squash beetles

The first big clue that they are not Mexican bean beetles is that they are on my zucchini, not on beans. Squash beetles eat plants in the squash family, like zucchini, squashes, and cucumbers. Bean beetles eat plants in the bean family.

Another is that their babies, also called larvae, have dark spines. The spines on Mexican bean beetle larvae are yellow, with dark tips as they get older.

Another clue is the method of eating. Both the babies and adults often gnaw a trench around the patch of leaf they are getting ready to eat. You may notice semicircular lines at the edges of damaged leaves.

One theory about why they do this is that the trenching prevents sap from running into the desired area. The sap may carry nasty chemicals that would interfere with the beetles’ eating.

Organic control of squash beetles

For now, I am hand-picking and smashing the beetles, both adults and larvae. The damage on my plants isn’t severe, and the number of beetles is low. Today, I found and smashed seven adults and one larva.

If the infestation gets bad enough that smashing is insufficient, there are a couple of organic-approved options to try. University of Connecticut agrees that hand-picking can work in small gardens but suggests that products containing spinosad might help if a beetle-damage gets very bad.

Another pest in my garden right now is armyworms

Armyworms have eaten all the leaves in this patch of cleome. — Armyworms have eaten most of the leaves in this patch of cleome.

I found armyworms in the garden today, too.

They were on both patches of cleome (spider flowers), and they haven’t left many leaves. When I realized what the pests were, I removed all the plants, with caterpillars attached, and stuffed them into a large bag.

That bag is now sealed up and ready for the municipal compost truck to pick up on Friday.

Armyworms can eat a garden to the ground in just a few days, which is why extreme steps are needed. If you see these in your garden, do not delay even one day in removing them!

Better news in the garden

First leaves on carrot seedlings are strappy and narrow; the next leaves are more feathery. PHOTO/Amygwh

Elsewhere in the garden, the carrot seedlings are sending up the “true” leaves that come after the first leaves. The first leaves that come out of a seed rarely look like the leaves on a mature plant.

For carrots, the first leaves are narrow and strappy. They are the ones that unfolded out of the seed, which is why the first leaves are often called seed leaves.

Do you see the seedling on the far right in the photo? The one leaf that is wider and more feathery gives a clue what the mature leaves will look like.

Also in the garden, there are tiny caterpillars on the pipevine plant. I planted the pipevine with these caterpillars in mind. If all goes well, a few of them will survive to become pipevine swallowtail butterflies, which are beautiful.

Caterpillars on a leaf of pipevine. If all goes well, they will mature to become pipevine swallowtail butterflies. — Caterpillars on a leaf of pipevine. PHOTO/Amygwh

Many Kinds of Chicory

27 August, 2018 by amygwh

My family has been growing and eating chicory for years.

Some of the many kinds

The first variety I grew may have been ‘Italiko rosso’, a loose-leaf type with red leaf-veins running through its dark green leaves. Others have been ‘Pan di zucchero’, a less bitter variety that makes a head like Romaine lettuces, and ‘Catalogna’, an all-green loose-leaf type. Including chicory in our meals turns out to have been good practice for traveling in Italy, because at restaurants we visited, the cooked greens served with the second course of a meal often were chicory, not spinach.

Emptied seed packets for two kinds of chicory. — Bringing home seeds from Italy isn’t allowed, but these two packets were emptied prior to travel. The packets are 7.5 x 4.5 inches — huge!

Radicchio, a heading-plant that is usually red instead of green, is also a kind of chicory. Endive and escarole are other forms of chicory that are familiar in the U.S.

These are all good to think about right now because they are cool-season crops that we can plant in our fall gardens. In general, the loose-leaf forms mature in 45-55 days, and so do most of the radicchios. Those can be planted in my area (zone 7b, with a first frost around Nov. 1) in a couple of weeks.

The heading type ‘Pan di zucchero’ takes 80 or more days to mature — it should already be coming up in the gardens of anyone nearby who wanted to grow it. Gardeners south of Atlanta, with later frost dates, still have time to get that variety started.

All of the above chicories are grown for their leaves, which are a lot less bitter in fall/winter/spring than in summer.

Chicory in the kitchen

I haven’t served chicory as a pile of cooked greens, Italian-style, at home, even when they haven’t been bitter. I am not a huge fan of cooked greens. Instead, I usually add raw leaves to a salad or to soups or sauces, where they end up cooked.

If I were going to cook chicory as a “mess of greens”, I would drop them into boiling water, let cook for about half a minute, drain off the water, then finish cooking in fresh water, just like for any other potentially-bitter green (collards, mustards). When we cook greens this way (because Joe does like greens), much of the bitterness goes down the drain with the water that we pour off.

The chicory in my garden right now

This year, I planted seeds for ‘Magdeburg’ chicory, a variety that has a bigger, tastier root for making chicory coffee.

The seeds went into the garden a few weeks before we left town, but the seedlings were not big enough for me to mulch their patch before we left for the summer. When we got back, the patch was a weedy mess. Among the weeds, though, were some chicory plants.

I weeded as carefully as I could but ended up pulling some chicory plants with the weeds in spite of the care. A few days later, yard-bunnies found the patch and nibbled it nearly to the ground. Wild yard-bunnies can be hard on a garden.

Deciding what to do about wildlife damage is not easy. There are many options for “pest control”, most of which don’t work. In the end, I poked some sticks into the ground near each plant, thinking that the sticks would be an annoyance for the bunnies.

As the plants regrew, the bunnies returned. Last week, I added a lot more sticks to the bunny-blockade. The more-crowded assemblage of sticks looks strange, but it seems to be working.

If all else fails and the bunnies are undeterred, I may be able to find a patch of wild chicory to use in making coffee. The bright blue flowers are easy to spot. The hard part will be finding a patch in an unpolluted place (not by a road, for example), where I can get permission to harvest the roots.

Chicory flowers are the same here as in Italy. — Chicory flowers in Italy are the same as those that grow wild here. PHOTO/Amygwh

Summer Squash in the Southern Garden

11 June, 2018 by amygwh

One of my most-favorite lines ever in a UGA Extension publication is about summer squashes. The line is in a table that lists recommended varieties for each type of crop. It says, for which varieties of summer squashes (including zucchini) to plant in the garden, “all are good and easy to grow.”

This line still makes me laugh. In a way, it matches my experience. In early summer the plants look great and produce plenty of flowers and small squashes. Unfortunately, it could also read “all are finicky and frustrating to grow”, since many summer-squash plants seem to drop into wilted piles of yellowing leaves in mid-summer, long before we have eaten too much squash. When I first started gardening in Georgia, I was lucky to get five or six good-sized squashes from a plant before it keeled over.

Southern Vs. Northern Experiences with Summer Squash

I am not the only Southern gardener to be troubled by a too-small squash harvest or plants that die too soon. However, Northern gardeners do not seem to have this problem. The complaint I hear from Northern gardeners is quite the opposite – they have mountainous harvests of zucchini and yellow squashes that keep coming all summer long.

Really, the complaint is one that doubles as a brag – their squashes are so very productive that, when the harvests begin, it is risky to leave your car windows open. The risk is that gardeners who have a superabundance of squash are likely to drop a large bag of squashes into the car as “a gift”.

Legend has it that over-squashed gardeners also will fill a bag with squashes, hang the bag on the doorknob of an unsuspecting neighbor’s home, ring the doorbell, and run. By the end of August, people are totally tired of squashes, especially zucchini.

I have never had so much summer squash and zucchini that I was not happy to find another one in the garden. Happily, as I have gained experience and understanding of what is going on in the garden, my plants survive longer and the harvests are larger. I have found that it is possible to have plenty of summer squash in the Southern garden, with a little planning.

Problems with Summer Squash in the Southern Garden

Squash Vine Borers

These are the cause of much anguish in the squash patch. The borers are larvae (caterpillars) of a day-flying moth that lays its eggs on stems of our squash plants. When the eggs hatch, the babies bore into stem, where they eat the soft part of the inside of the stem. The borers seem to not eat the toughest fibers, because one sign that borers have caused your squash plants to wilt is that the stem looks frayed. You may also see some frass (caterpillar poo), a golden-orange-brown, granular-looking mush, around or in the damaged section of stem.

What to do? If the plant is already a wilted mass of yellowing leaves, it may be too late to save the plant. If, though, you look at the lower part of a squash stem, see little holes in the stem and maybe a little frass nearby, but the plant looks otherwise healthy, it is not too late!

Step 1:

Locate the sharpest blade on your pocket knife and use it to make a long slit in one side of the squash stem. The slit should run lengthwise on the stem; it should start below where the damage seems to be and extend above the damaged area. Use the tip of the knife blade to pry the slit open, so you can look inside and find the squash vine borers. Use the knife tip to remove (or kill, depending on your philosophical stance on garden pests) the borers from the stem. You might find just one, but you might find a half dozen or more.

Step 2:

Saturate the inside of the stem with a product that contains Bt for caterpillars (Thuricide is the brand I have been using – bought a few years ago and still works), and spray up the length of the stem on the outside, too. If any borers are still alive inside the stem, the Bt for caterpillars (organic approved) should reverse that status fairly soon. If your Bt is powder form instead of liquid, do your best to fill the stem with the powder, and then liberally apply it along the outside of the stem.

Any Bt applied on the outside of the stem will wash away in the next rain or watering-event, so you might want to re-apply it a few times.

Step 3:

Mound up garden soil over the damaged section of stem. If you are feeling very industrious, you can try wrapping the damaged section with aluminum foil, but I find that just piling up some good soil over the damaged stem protects it from invasion by other pests. Also, squashes sometimes will send out new roots along buried sections of stem.

Step 4:

Consider the health-status of your plant. Summer squash in the Southern garden should be lush, with huge, dark green leaves. In my garden, the largest, fastest-growing squash plants survive squash vine borer damage much better than less-lush plants. If your plants are on the puny-side, side-dress with some organic fertilizer or a shovel-full of compost or composted manure.

Squash Bugs

Squash bugs look a lot like stink bugs as adults. As youngsters, they are called nymphs, and they move around in groups. The nymphs do not look at all like the adults, but if you see groups of insects scuttling around on your squash plants, they probably are squash bug nymphs.

Squash bug eggs on a leaf of summer squash in the Southern garden — Squash bug eggs on a leaf. PHOTO/Amygwh

These feed on the squash plants – leaves and fruits – and they can cause a lot of damage. An even bigger problem is that they can carry a squash disease called Cucurbit Yellow Vine, which can definitely kill your plants.

The adults and nymphs can be removed by knocking them into a tub of soapy water. It is a good idea, though, to check your plants for squash bug eggs.

You can use a piece of clear packing tape or a piece of duct tape to remove the eggs from your plants. Just press the sticky side of the tape to the collection of shiny eggs, remove the tape, fold it over, and smash the eggs inside the tape. Simple!

Removing all the eggs will help keep the population of adults and nymphs to a much lower level, which will limit the amount of damage they can do to your plants and reduce the risk of Cucurbit Yellow Vine.

Mildews

Summer squash in the Southern garden also is attacked by mildew diseases, both downy mildew and powdery mildew. If your plants die earlier in the summer, then these will not be a problem, because the mildews usually appear after mid-summer.

Downy mildew arrives at a slightly different time each summer in upper parts of the South. It can’t survive our winters, but it comes up from Florida where it survives just fine. If the petioles (leaf stems) are still standing up on your plants, but the leaves look brown and droopy, then downy mildew is a likely cause. There is no effective spray or treatment for downy mildew, but preventive care can help.

Leaf diseases like downy mildew (and powdery mildew) need leaf wetness to infect the leaves and grow. Keeping the leaves dry as much as possible, by careful watering, can delay infection. Increasing air-flow around the leaves, so they dry faster after a rain, also helps. Remove weeds as much as possible, and allow plenty of space between plants.

Also, healthy, well-grown plants get less disease than puny plants. Just like for squash vine borers, consider whether you might need to side-dress your plants with fertilizer or compost to improve their condition.

Powdery mildew becomes a big problem in warm, humid conditions. Since that pretty much describes several months of weather across the entire Southeast, it is a safe bet that powdery mildew will find your plants eventually.

Treating Mildews in Organic Gardens

For both downy and powdery mildews, the bacterial product Serenade, which is organic-approved, can slow down the rate of infection. It should be applied to plants every 7-10 days, before any sign of infection is seen. If you see signs of disease on your plants (mottled or brown spots on leaves, for example), it is too late to get much benefit from using the product.

In a couple of Cobb County community gardens, the use of Serenade has helped extend the “squash season” for local gardeners. If your squash patch has suffered from mildew attack in past years, you might consider trying the spray, but do not wait much longer to start. By July, infection may already have begun.

Another option is to spray with homemade products of either compost tea (one gallon of well-aged compost in a five gallon bucket filled with water, soaked for three days, then strained to use in a spray bottle) or a baking-soda spray, both of which can slow down an infection. Neither of these has been shown to work as well as Serenade (which works less well than chemical fungicides), but some gardeners like to try the DIY route first.

If you are a DIY gardener, this is the recipe for baking-soda spray recipe from one of my Rodale gardening books:

Dissolve 1 teaspoon of baking soda in a quart of warm water, with up to a teaspoon of dish soap or insecticidal soap added. Spray the leaves, including the undersides.

If you would rather treat your garden crops with compost tea but do not currently have a source of good compost, try the Sustane Compost Tea Bags. Not-needing to strain the finished compost tea before using it in a spray bottle makes the “tea bags” extra-convenient.

For both compost tea and the baking soda solution, apply to plants much more frequently than the Serenade.

Hoping for Plenty of Summer Squash from the Southern Garden

Summer squashes seem to be an essential vegetable in the South. They are the base of many favorite “church casseroles” – dishes that fill the tables at summertime potluck suppers and appear at your door in hard times. I don’t remember seeing squash-casseroles when I was growing up in Oklahoma, but I certainly have seen (and enjoyed) many since moving to Georgia. In the South, the squash harvest is important.

The garden/farm where Joe and I used to volunteer got around squash-plant losses by planting MANY squash plants over several weeks. Even when some plants died, more remained and produced squash. If the squash harvest didn’t look abundant enough, we just planted more.

In home gardens, this approach is not really feasible. Hence, the long blog post about upcoming problems with summer squash in the Southern garden.

Best wishes for a squash-filled summer!

-Amy

Striped Caterpillars in the Garden, Eating the Dill

12 May, 2018 by amygwh

Several weeks ago, while I was working in the garden, a battered, tattered black swallowtail butterfly flitted into my dill patch. While she was there she laid some eggs. Eventually, some of those eggs hatched, and then there were caterpillars in the garden, eating the dill.

They ate and ate. After awhile, some of the caterpillars disappeared. I assume other wildlife, such as birds, ate them. The last time I saw them, a few days ago, there were three left, fat and striped and still eating the dill.

Caterpillars in the garden are not always a problem. This one will be a black swallowtail butterfly. — PHOTO/Amygwh

They have all gone now, which means I can finally harvest the dill. The plan is to dehydrate most of it, for use this winter. I am thinking of using it on fish, in particular. It is also good in spanakopita, but I don’t eat cheese like I used to, even feta, so that recipe is no longer “in the rotation”.

What to do about caterpillars in the garden?

Even if these striped caterpillars were more voracious eaters, gnawing my dill plants down to little nubs, I probably would just make a note to plant a lot more next year. Accepting some insect-damage is part of the organic gardening way.

In addition, the world has been losing pollinators over at least the past couple of decades, probably longer. Even though butterflies are not our most effective pollinators, removing these with either an organic pesticide or a mechanical method like smashing would not be good for the future of food in the world.

Luckily, the caterpillars have left plenty of dill for us humans.

When other caterpillars in the garden eat so much that a plant is nearly bare of leaves, then control measures may be desired. As usual, the first would be to keep the adults, the butterflies, away from the plants completely. Draping small-meshed netting or a spun row cover on a support structure over the plants can keep adult fliers away (see post about cabbage butterflies and moths).

What else do these caterpillars eat?

These caterpillars are sometimes called parsley worms, because they eat many plants that are in the parsley family. If you guessed that one of those plants is parsley, you are right! Fennel and carrots are other garden plants in the same family, as is dill.

University of Florida has published a fact sheet about the Eastern black swallowtail butterfly, its lifecycle and ecology. The fact sheet includes a list of other plants these caterpillars will eat. Some are native plants, like mock bishop weed and water hemlock. Some are not native across the entire U.S., but have been introduced. One that many people will recognize is Queen Ann’s lace.

Where did the caterpillars go?

Surprisingly, Joe and I found a chrysalis way across the yard, in a flower bed, on Thursday. I almost never find these, so this one made my day.

Chrysalis of black swallowtail butterfly from 10May2018, in Georgia. PHOTO/Amygwh

The chrysalis is on a leaf of a hardy amaryllis, given to me by my mother-in-law many years ago.

Which beautiful pollinators are in your garden?

Ladybugs in the Garden – Which Ones Are They?

6 May, 2018 by amygwh

My garden has been full of insect activity recently. There are lovely, tiny, metallic flies, some shiny black wasps, also tiny, and a few bees. I have also seen several ladybugs in the garden, plus some ladybug babies (larvae) and pupae (where larvae transform into adults).

Ladybugs are voracious eaters of aphids in the garden. Adult, larva, and pupa forms are very different in appearance. — Ladybug adults and larvae are voracious eaters of aphids. PHOTO/Amygwh

Which Species of Ladybug is in My Garden?

I am always happy to see ladybugs in the garden. They eat a lot of aphids. The adult ladybugs eat aphids, and the larval ladybugs eat aphids. For an organic gardener, this is a win-win combination!

Many of us would much rather rely on predators like ladybugs than use even organic-approved sprays.

When I decided to find out which ladybug is most common in my garden, I took a lot of pictures and then searched online.

My ladybugs mostly have about 16 spots on their backs, so it was easy to eliminate “two-spotted ladybug” from the list of possibilities.

Even better, university-based websites agreed that the black “M” shaped marking behind its head was a defining feature. It means my ladybugs are Asian multicolored ladybugs. At least, the adults are.

Apparently, this is a ladybug that tries to overwinter inside buildings; in winter it is considered a pest. In summertime, though, in gardens and farms, it is a big help in removing aphids from crops.

This University of Kentucky page includes pictures of several kinds of ladybugs. Maybe the ladybugs in your garden will be native, and not imports like mine!

Why Are Ladybugs in the Garden, in Georgia, from Asia?

Apparently, various people brought these ladybugs to the U.S. on purpose, to help control pests like aphids and soft scale insects. According the University of Florida and the USDA, these ladybugs were released here many times in the past. The first time may have been a hundred years ago! The multicolored ladybug finally established permanent populations in the U.S. in the late 1980s to early 1990s.

Plenty of Work for Ladybugs in the Garden

My kale, especially, has been hit hard by aphids. Luckily, we have already eaten quite a lot of the kale ourselves. The current plan is to harvest the rest of the kale, wash it very well, and eat it soon. Any we don’t use on tonight’s pizza will get stashed in the fridge to use tomorrow.

Meanwhile, I have seen aphids on the milkweed — planted for the butterflies — and a few on leaves of the iris. Aphids also can be pesky in the fall; they are not just pests for the spring. My garden will probably feed a lot of ladybugs for many weeks to come.

Organic Pest Control: Mexican Bean Beetles

29 April, 2018 by amygwh

Mexican Bean Beetles can strip all the green tissue off bean plants surprisingly quickly. If your organic garden is attacked by these pests pretty much every year, odds are high that you will see them again this summer.

Mexican bean beetles have stripped green tissue from most of leaves in this bean patch. PHOTO/Amygwh

How can you recognize these pests? The adults look a lot like ladybugs, only more orange or yellow. Their babies (aka “larvae”) are bright yellow, and look a bit like stubby, spiky caterpillars. (See the picture collage lower in this post.) The damage to the leaves, which become very brown as the beetles and their babies eat the green plant tissue, is the clue most gardeners notice first.

Having some strategies in place, before the bean beetles arrive, can help organic gardeners to harvest plenty of beans in spite of the coming pests.

Strategies for controlling (or minimizing) an attack by Mexican bean beetles have some overlap with those for some other pests, such as aphids or the caterpillars of cabbage moths and cabbage butterflies.

Using Barriers to Keep Mexican Bean Beetles Off the Plants

For caterpillars like cabbage worms and loopers (babies of the cabbage moths and butterflies), we can use netting over our plants to keep the adult flyers away. If the adults can’t reach the plants to lay eggs on them, then we won’t have caterpillars on the plants.

For Mexican bean beetles, we can adapt this strategy by using a floating row cover instead of netting over the bean plants. The non-woven construction of the fabric means there are no holes for insects to sneak though. The row cover is lightweight and can be draped right over the plants, but it seems kinder to the beans to secure it over a support structure. The bean patch needs to be weed-free before the area is covered. Beans, in general, are self-pollinating; most varieties will make beans even when bees and other pollinators can’t visit the flowers.

Waiting for Parasites and Predators

There is a parasitic wasp that lays eggs inside the larvae of the bean beetles, just like there is a parasitic wasp that lays its eggs inside aphids. Sadly, the bean-wasp doesn’t seem to hang out in my yard, even though my garden gets attacked by Mexican bean beetles nearly every summer. Arbico Organics sells “mummies” (Mexican bean beetle larvae that contain wasp eggs/babies) as a bean-beetle-control for use on farms, but this is a very expensive option. It also is not really practical for home gardeners. Many of us are not growing even the minimum 70 square feet of beans per mummy recommended to make this work. It is nice, though, to know that there are insects working on behalf of farmers and gardeners to control these pests.

Spined soldier bugs and assassin bugs eat Mexican bean beetles, too. Some of these could already be present in your organic garden, but probably not enough. Certainly, there are not enough of these helpful predators in my own garden.

Stages of Mexican bean beetle infestation on bush beans, with a suggestion to alter timing of planting to harvest plenty of beans in spite of the beetles.

Insect-eating birds also can help reduce the population of bean beetles in the organic garden. In my bean patch, wrens move through the patch, hidden from my view below the canopy of leaves. All I can see is movement of the tops of the plants, until the wrens spring into flight after eating. It is great to know that these garden helpers are in action.

However, the birds seem to leave a lot of beetles uneaten. Maybe Mexican bean beetles are not very tasty.

Using Pest Control Products

In general, organic spray-type options for insect pests are not very effective, and options for beetles are worse. Spraying the undersides of the bean leaves with insecticidal soap (not an easy feat!) may kill the youngest larvae.

If you are desperate, try a product that includes Neem. Neither version of insecticidal soaps will have much effect on the adults, though.

You may have better luck than me at applying a spray to the undersides of leaves. If so, then insecticidal soap could slow down an infestation in your garden. Personally, I do not use a spray option.

For me, hand-smashing the larvae and eggs seems to slow down an escalating infestation about as effectively as using insecticidal soaps. So does knocking adults into a tub of soapy water, where they will drown. In other words, none of these options is super-effective.

Adjusting Your Planting Dates

This is the strategy that has given me the most abundant harvests. This strategy requires that gardeners plant their bush beans early — right around the estimated last-frost-date for their yard. This strategy allows gardeners to begin harvesting beans as soon as possible.

Mexican bean beetles don’t typically become abundant until sometime in the first half of July in my garden, and my estimated last frost is around mid-April. Planting near this date, when it can still be very cool, lets me bring beans to the kitchen beginning at the end of May, through all of June, and into early July, before bean beetles destroy the crop.

When the Mexican bean beetles have shifted from just feeding on leaves to also feeding on the beans, it is time (or past time!) to remove the crop completely from the garden. Be sure to clear it all away. Plant something else in this spot.

In 2-3 weeks, in another part of the garden, you can then plant a second crop of bush beans. In my garden, this second crop is untroubled by Mexican bean beetles. It does, eventually, get bean leaf rollers, but those do a lot less damage to the bean plants and they never eat the beans.

Potassium Sources for an Organic Garden

9 February, 2018 by amygwh

Potassium is one of the Big Three nutrients that plants need in large amounts (the other two are nitrogen and phosphorous). These are the essential nutrients that are represented by three numbers, such as 5-10-15, on bags of chemical fertilizers.

If you’ve had the soil of your organic garden tested and learned that it is very low in potassium, you may be looking for ways to boost the amount of this essential plant nutrient in your organic garden.

The good news? There are several good sources for potassium available for organic gardens.

Greensand – This is a mined product, made from natural deposits of a marine sediment called glauconite. It is smashed into very small bits (making it into “sand”) for you to mix into your soil. The potassium content can vary between brands. You will need to read the label of your bag to know how much potassium (the percentage) is in there.

Greensand is a potassium source for organic gardens.

Greensand does not contain any nitrogen; some brands may contain a tiny bit of phosphorus, but not enough to really count if your garden needs phosphorus, too. The potassium is released SLOWLY, so if your garden’s need is dire, you might want to use a faster-release potassium source along with the greensand.

When I make my own organic potting mix, I add a little greensand (about a half cup for a 6-gallon batch of potting mix). McGee and Stuckey, in their book The Bountiful Container, also recommend adding a bit of greensand to organic potting mixes.

Wood Ashes – This is a fast-release and FREE source of potassium for home gardens. Wood ashes may be as much as 3-7% potassium! This is similar to the percentage in many bags of greensand (my current bag has less), making wood ashes an option to consider for gardens that need a lot of potassium Right Now. The potential drawback to this organic potassium source is that it will raise the pH of your garden’s soil.

Did you have the soil from your organic garden tested this year? If you did, you will have a record of the soil pH, which is how acidic or basic it is. A pH number below 7 is acidic. A pH number higher than 7 is basic. Most garden vegetable plants will be more productive when grown in soil that is in the 6-7 pH range (slightly acidic). If your soil pH is already in that desired range — or higher — then wood ashes are not a good potassium choice for your garden.

Sul-Po-Mag – This is another mined source of potassium, available to gardeners as bags of pulverized rock. The name Sul-Po-Mag is shorthand for the longer name of Sulfate of Potash Magnesia. This has a very high percentage of potassium, as much as 22%. Even though it is from rocks, it is considered a fast-release source. If your organic garden needs a lot of potassium right away, and the pH is high enough that wood ashes are not a good choice, then this may be what you want. Sul-Po-Mag also provides sulfur, magnesium, and some micronutrients. This product is generally pH-neutral, meaning that it will not swing your soil’s pH in either direction.

Locally, we have used Sul-Po-Mag when mixing up batches of organic fertilizer for community gardens that have a soil-pH higher than 7.

Kelp Meal – This is a slower-release source of potassium. It is not a concentrated source (about 1% potassium), but it also provides nitrogen, phosphorus, and a host of essential micronutrients that can improve the nutrient state of poor soils. If you are working with native soil, in an in-ground garden in the Southern US, and your organic garden is fairly new, you may want to choose kelp meal as your potassium source. In my area, the clay soils are all worn-out (decades of cotton fields) or washed-out (erosion from high rainfall), and benefit greatly from a dose of kelp meal.

How much of any of these should you use? If you have a report from a soil lab, the recommendation it offers for a chemical fertilizer can be converted to organic amendments, if you are reasonably good at math. The linked UGA publication includes the equations to use. I have done these conversions for our local community gardens.

An alternative is that you mix up a batch of organic “10-10-10” (or another listed formula), following the recipe in the above-linked UGA publication about converting to organic amendments. The recipes on the last page of the document list options for the nitrogen source (pick one from the list), options for the phosphorus source (pick one), and options for the potassium source (pick one).