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tomato diseases

What Caused my Tomato Plant to Wilt, Part 2

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One of my two mature, productive tomato plants wilted last week. Surprise! My previous article (was it just five weeks ago?) about wilting tomato plants was more timely than I knew.

This is the story of what happened.

Wilted, green top of tomato plant
The whole plant had wilted. See the droopy leaves up top?

We had rain. The rain in our area has been patchy, so the rain in my yard may not be like the rain in your yard, but one day we had about 10 hours of steady rain. When I looked out the front windows the next morning, thinking that the garden would probably look great after all that water, I saw that one of my tomato plants had wilted.

I thought back to my previous article about the steps to follow, to figure out what happened to my plant.

At the very least, I can say with confidence that dry soil was not the cause of the wilting.

The plant hadn’t wilted only on one side, and it wasn’t merely slightly droopy. All the leaves on the entire plant were hanging limp on the branches, and smaller branches were sagging.

Tomato stems suspended in jar of clear water.
The streaming test for bacterial wilt was negative.

At first, I thought “cool, bacterial wilt”, since the wilting was so sudden.

Checking for Bacterial Wilt

This is a disease I have seen only once, but I knew that one sign of bacterial wilt was sudden wilting of the entire plant.

Often, this wilting takes place in hot weather and moist soil.

I trimmed off leaves and branches to do the bacterial wilt streaming test. If bacterial wilt was the cause, then white cloudy ooze should stream out of the branches when they were suspended in water.

When the first couple of leafy branches failed to produce the white cloudy streaming that I expected, I cut a thicker section of stem to add to my jar of clear water, to see if maybe I just hadn’t used a big enough section of branch. Ten minutes later, the water was still clear.

Looking at base of the plant for more clues

Then, I finally looked at the base of the plant, where the stem emerges from the ground. This was when I thought “uh oh”. There was white fungus-looking stuff right near the base of the plant and climbing up the stem.

White stuff on ground and on two green stems growing through the white stuff

To be honest, this is probably a bigger problem than bacterial wilt would have been for the future of my garden. My knowledge of white fungus climbing up stems from the ground leads me to think the fungus is Southern Blight. (Link is to a pdf about Southern Blight from University of Kentucky)

White fungus climbing up green tomato stem and extending into nearby soil

Lots of fungal diseases are host-specific. That means that they can infect only a limited number of crops. Southern Blight, on the other hand, can infect many kinds of crops.

How can I reduce future damage from Southern Blight?

I already removed the plant, including as much of the root system as I could. University of Kentucky’s information (linked previously) recommends removing the soil in that area, too, to reduce the number of reproductive bits, called Sclerotia, in the garden.

The next recommendation that organic home gardeners can follow is to grow plants that can resist Southern Blight in that area for a few years.

Resistant plants, according to University of Florida and Louisiana State University include woody plants, ornamental grasses, corn, and wheat.

The other recommendation is to raise the soil pH a bit. The fungus grows more slowly in higher-pH soils.

The good news: no evidence of root-knot nematodes

Smooth roots from dug-up tomato plant
Smooth, tapering roots show no evidence of root-knot nematodes.

If there were root-knot nematodes adding to the damage, the roots would look lumpy. Maybe other gardeners are not as relieved as I am to see this lack of lumpiness, but some years my garden is seriously affected by the nematodes.

Where did the Southern Blight come from?

This is hard to know. My garden has never, until now, shown any sign of harboring Southern Blight. The disease can travel on infected plants, mulches, soil, and contaminated tools. I am thinking that it could also be spread by ground-scratching birds, but they are not mentioned in any of the publications I checked.

A new tomato plant growing nearby

At the end of June, when we returned from five weeks of travel and before we drove across Texas to visit family in the Austin and Houston areas, I planted two tomato seeds in the garden. Luckily, they are in a separate garden bed from the blighted plant.

I set the seeds inside a collar formed by a paper cup that had the bottom removed. The collar was to help hold moisture and to protect the seeds from being eaten. I watered the area well before we got in the car and headed west.

Small tomato plant next to a stake, and several Swiss chard plants planted in an arc nearby
Healthy, young tomato plant was started from seed in late June.

Amazingly, when we got back from our 8-day tour of relatives, a little tomato plant was standing where I had planted those two seeds.

I had planted some Swiss chard and a leaf-amaranth in the same little garden area, and they were coming up, too. A caterpillar of some kind found those to be delicious, so I had to replant the greens, but all is looking good now.

That little tomato plant has flowers on it today. If all goes well, there will be more garden-tomatoes coming into my kitchen by late September, and, hopefully, the potential disaster of Southern Blight will not be causing too many more problems.

What Caused my Tomato Plant to Wilt?

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Some varieties of tomato die in my yard. The most obvious sign of their impending doom is wilting. The presence of many dead leaves is another easy-to-notice sign.

Wilted green leaves on a tomato plant.
Wilting of tomato leaves can have many causes.

When a tomato plant starts to look extra-pathetic, figuring out the cause is important. Sometimes, the plant can be saved. More often, it can’t, but knowing the cause can help the gardener prevent problems in the next-summer’s garden.

This article describes the way I figure out what is wrong with an ailing tomato plant.

Wilt versus leaf roll

Stressed plants will sometimes roll or curl their leaves. This is different from wilting. In the leaf roll response, leaves roll or curl upward at the edges. The roll can be extreme, so that each rolled leaf is almost cigar-shaped, with the lower leaf surface seen on the outside of the roll.

University of Washington’s publication on leaf roll in tomatoes explains that this sign has several possible causes, that are not diseases, including high temperatures and fluctuating soil moisture levels, and that it is more common in indeterminate plants than in determinate plants.

Wilted leaves, unlike leaves doing the leaf roll thing, do not roll inward/upward.

Wilting caused by something other than disease

Wilting in tomato plants can have non-disease causes.

Soil moisture

The obvious first thing to check when a plant looks wilted is the soil moisture level.

Tomato plant standing in water puddle
Too much water.

It makes sense to pretty much everyone that a plant might wilt in dry soil, but when soil is too wet, that can also cause wilting due to roots that have drowned and no longer work to pull water into the plant.

If you aren’t sure about the soil moisture level, poke a trowel down into the soil not too far from the wilted plant, then pull back on the handle to make an open wedge that your hand will fit into. Reach down into the soil with a bare hand to check for dampness.

Too-dry soil is one cause of wilting that a gardener can fix. Too-wet soil is less easy to fix quickly, and a drowned root system takes a long time to overcome.

Damage to the main stem

If a plant is wilted, another thing to check after soil moisture is whether the main stem is damaged.

tomato stem showing wound
Plant may wilt above a wound on the stem.

If the main stem is very damaged, it is possible that the plant’s water-conducting tubes have been damaged, too, and can not move water well-enough through the plant.

A damaged tomato-stem cannot be fixed. If the damage is near the ground, caused by a mechanical injury (being bumped or scraped), raising up a mound of soil above the damaged area may help.

Tomato plants can make new roots on the main stem,. The mounded up soil can allow new roots to form above the damage. Growing new roots takes time, though. The tomato harvest may be slower to arrive and smaller than for a plant that didn’t have a delay.

Loss of roots due to gophers

Gophers can ruin a garden, plant by plant. They burrow underground and eat plant roots. Most of us will not ever have this problem in our gardens, but gophers were my second stepdad’s garden nemesis.

Gophers usually leave mounded trails through the garden. If a plant simply falls over one day, and you discover that its roots have disappeared, look for the trails.

A plant that has lost its roots to gophers won’t recover.

Wilting caused by diseases in the soil

The next step, if all of the above do not seem to be the cause of wilting in your tomato plant, is to dissect the plant for a closer look.

Cut across the main stem near the ground, and look inside the stem. Is the tissue a healthy greenish-white all the way across, or are there some brown areas inside the stem?

Fungus underground

Cross section of tomato stem showing brown sections inside the stem; evidence of a fungal wilt disease.
Cross section of tomato stem showing the browned areas that are evidence of fungal wilt disease.

The two fungal diseases that cause most of the wilting in tomato plants that I have seen in Georgia are fusarium wilt and verticillium wilt.

To be honest, I usually cannot tell which one has caused the trouble, but both will show browned areas inside the stem that are where the fungus has entered the plant through the roots and clogged up the water-conducting tubes.

These diseases cause more trouble in very wet soils.

I have grown the heirloom tomato variety ‘Mortgage Lifter’ in both wet and dry years. In dry years, the plants are productive and make delicious tomatoes through the whole season. In rainy/wet years, the plants die from one of these fungal wilt diseases by mid-July.

EDIT from 20 Aug 2019 – A new soil-borne fungus that attacks tomato plants has shown up in my garden. See my article “What Caused my Tomato Plant to Wilt, Part 2” to read about Southern Blight in my garden.

Bacterial wilt

Bacterial wilt causes rapid wilting of the whole plant. If your plant has wilted completely, seemingly overnight, this is a cause to suspect.

University of Florida’s information on bacterial wilt describes a simple stem-streaming test that you can do at home, to check for this disease:

Cut a stem from the wilted plant and suspend the cut end in clear water. White, cloudy material oozing out of the cut end into the water is a sign that the plant is infected by bacterial wilt. If nothing oozes out of the stem, then bacterial wilt is not the cause of your tomato plant’s wilting.

I have only been able to confirm bacterial wilt as a cause of tomato wilting once, in someone else’s garden, in my many years of looking at wilted tomato plants. That makes me think that this cause of wilting is not super-common.

Wilting caused by nematodes in the soil

Root-knot nematodes — microscopic wormlike creatures — are another possible cause of wilting in tomato plants. If all of the above-ground parts of the plant check out as being fine, except for the wilting, the next place to look is the root system.

Dig up the roots of the wilted plant, and examine them carefully. Healthy roots are creamy white in color, and they are fairly uniform in diameter, gradually decreasing in width as you follow them to the growing tips.

The roots of tomato plants infested by root-knot nematodes are lumpy, looking a bit like they have swallowed large beads.

The University of Arkansas publication (pdf) about root-knot nematodes includes photos of healthy and infested roots, side by side, for comparison. If your plant’s roots are lumpy, then root-knot nematodes are the likely cause of wilting.

Wilting caused by leaf diseases

All of the above causes of wilt can include some yellowing of the leaves, but not brown spots on the leaves. If a tomato plant has many wilted, yellowing and/or browned leaves, and it also has a lot of spotted leaves, then a leaf spot disease is a likely cause.

Leaf spot diseases can affect most tomato plants as the season progresses. These diseases tend to be worse in wet years than in drier years, but nearly every spring-planted tomato plant in the Southeastern US will show some signs of a leaf disease by the end of September.

  • Brown spots on tomato leaf are sign of leaf disease.
    Brown spots on tomato leaf are a sign of leaf disease
  • Tomato plant with nearly all brown leaves
    Too many dead leaves; this plant will not recover.

The brown spots on the leaves are an easy-to-see clue.

Cure for wilted tomato plants

Many of the causes listed above do not have an easy cure. Most of them, though, can be avoided in next-year’s garden with some planning.

If the garden soil is in a place that stays wet much of the time, raising it up a few inches can improve drainage and reduce the risk of the moisture-related wilt problems, like the soil-borne diseases.

Another simple step is to grow disease-resistant and nematode-resistant varieties. Many of these are hybrids, not heirlooms, but some heirloom varieties also survive just fine in my garden. Some will do fine in yours, too; however, finding them may take time.

Harvesting Summer to Make Room for Fall

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About 2/3 of my butternut squash harvest.    PHOTO/Amy W.

It’s been a busy weekend in the garden. To start, I harvested most of the remaining butternut squash. Six had already been brought inside, because the vine they were on looked “done.”

These in the photo to the right were also on some pretty dead-looking vines, but there are three more immature butternut squash out in the garden. After tracing their vines so I could determine whether they had a chance of further ripening, I left their vines behind when I removed the other, browned-out plants. So far, I have brought in about 25 pounds of butternut squash. That has opened up some space in the garden.

Browned vascular tissue caused by a tomato wilt disease.  PHOTO/ Amy W.

I also harvested all the remaining Amish tomatoes, even the green ones. In last week’s post I had mentioned that the plant had a lot of yellowed, drooping foliage, and it was time to pull up that plant.

After slicing through the stem to check on what had caused the trouble, it was easy to see the gunked-up vascular system, which often is caused by Fusarium wilt. A healthy stem would have been white or whitish-green all the way through, rather than being ringed inside with brown!

As space has opened up in the garden, I’ve planted some more seeds. Today I planted some kale, collards, lettuces, nasturtiums, and English peas. If they don’t do well from seed at this time, it won’t be a disaster, because I have started some of those in a flat already.

Caterpillar of the Gulf fritillary butterfly.  PHOTO/Amy W.

The English peas are part of yet another experiment. I harvested most of the popcorn, and as I was cutting the stalks down to chop up for the compost pile, I decided to leave them cut at about 3.5-4 feet high, for peas to climb up. The peas are planted in the rows between the cornstalks. It will be interesting to see how that space goes as the summer/fall progresses.

Elsewhere in the garden, we have some surprisingly unattractive caterpillars. They are dark orange with black spines, and they are busy defoliating the passionflower vine.

Bees loving a passionflower to smithereens. PHOTO/Amy W.

The caterpillars are the babies of the Gulf fritillary butterfly which also is orange, but it seems a lot prettier.

The passionflower vine is getting a lot of insect activity. In addition to being host to the spiky caterpillars, it also is host to some big, shiny carpenter bees that spend most of their days, it seems, loving on the purple flowers.

All that bee-loving action has resulted in the formation of a lot of “may-pops” on the passionflower vines. I am looking forward to trying those fruits!

Tomato Problems Abound

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The tomato-ripening has been slow to begin, but it finally is coming along at a faster clip. The Cherokee Purple tomatoes are big and beautiful; however, the plants on which they are growing look terrible. I wasn’t able to get a good picture of the tops of the two plants, partly because the plants are so tall and partly because it keeps raining. Aiming up results in a wet camera lens!

Many of the leaves are bedraggled, and there is marked wilting of some individual stems, while other stems continue to look just fine. I sliced into one of the wilted stems and saw brown in the vascular tissue (located between the green skin and the white, central pith). Those indications, along with the fact that the tomatoes continue to look good, leads me to believe that the problem is one of the soil-borne wilts, probably Fusarium. That is a huge relief, because I have heard that Late Blight (a very bad tomato disease) has been “going around.”

Great-looking Cherokee Purple tomato, finally ripening, on a very sad plant.  PHOTO/Amy W.

Ironically, the Costoluto Genovese tomatoes also look good, and also on a very raggedy-looking plant, but it has a completely different problem; it has a leaf-spot disease. I’m thinking that it is Early Blight, because the brown areas on the leaves continue to expand (slowly), and they get the typical concentric rings as they enlarge.

Costoluto Genovese tomatoes, on a plant with a leaf-spot-type fungus.  PHOTO/Amy W.

For the Cherokee Purple tomatoes, my current plan is to harvest all the big tomatoes and then pull up the plants. My next patch of bush beans will go in their place. I just need for it to stop raining long enough to manage the task!

The Costoluto Genovese tomatoes aren’t quite as far along. I keep hoping for a dry day (notice a theme here?) on which I can go out and trim away all the “bad” leaves and then see if there is anything besides fruit left to salvage after I complete the pruning.

While I was in Texas, the rain gauge out in the garden accumulated more than five inches of rain. The tomato-disease problems aren’t a big surprise, considering how wet it has been all spring and summer. However, they are annoying. Since the forecast is for more, and yet more rain, I am thinking that it is time to come up with a Plan B. Wish me luck?

Meanwhile, there is a little lesson here about these two varieties of tomatoes: Costoluto Genovese seems to resist Fusarium wilt, and Cherokee Purple seems to be resistant to Early Blight. In future years, that information might come in handy.

I hope that all the other gardens out there are having fewer tomato problems!

Finally, a Summer Harvest!

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I have been bringing in green beans for a few days now, and this is not the first pepper, and the zucchini isn’t quite full-sized, but today is the first day I could bring in more than one or two kinds of veggies from the garden in the same day.

In honor of the occasion, I have arranged it all in Grammy J’s cut glass bowl (Grammy J was my mother’s mother’s mother — my great grandmother). That is just how happy I am with the little harvest.

First real harvest of summer crops, 2013.            PHOTO/Amy W.

I brought in the regular bulbing onions today, too, but they need to dry a few days on the front porch before I trim and weigh them.

The 2013 harvest of bulb-type onions from my yard.        PHOTO/Amy W.

We’ve had crows in the yard over the past couple of weeks, which means that seedlings have been pulled up and tossed about. I’ve replanted some of the cucumbers (and melons, and butternut squash) more than once.

To protect the most recent batch, I cut the bottoms from small plastic cups then pushed the cups down around the seedlings as they emerged. This seems to have been enough protection; the smallest cucumber plants finally all have a couple of true leaves. This may be enough that they are no longer so attractive to crows.

At home and at the garden/farm where I volunteer, I have been pruning the tomato plants. If I can’t stand up tomorrow, it’s because I have been hunched over pruning leaves and suckers from about 150 tomato plants in the past couple of days. Here in the South, diseases are an ever-present threat to tomatoes. It can help if the plants are pruned up a bit.

I like to get them to the point that there are no leaves within about 18 inches of the ground, and I prune away leaves that are growing in toward the center of the plant, to create a cone of air-space in the center. This takes several weeks of work as the plants grow, but the improved airflow can help keep the remaining foliage drier and less susceptible to the most common airborne fungal diseases.

Hope all the other gardens out there are growing well!

Plant Health Management

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I went to a workshop about organic farming/gardening down at Fort Valley State University this past week. Most of the speakers addressed the administrative end of things – how to get a farm certified as being organic, who needs to get certified, who qualifies for financial help and where to get that help. That was all great information, but that wasn’t all we heard about.

Dr. Elizabeth Little, a plant pathologist with UGA, was also there, and her talk was very different. She said some things I’ve been trying to tell people for years, but she said it all better and with the authority of a PhD who has been doing actual, official research into the topic. The gist of it was this:

There are no organic products that REALLY work for disease management; switching to organic farming or gardening isn’t about simple substitutions of one chemical for another. Essentially, in organic operations, it’s all about prevention.

The organic farmer/gardener takes a systems approach to plant health – based on fertility, plant selection, crop rotation, sanitation, and site selection. The organic system also relies a lot on biological interference with disease; by promoting a good ecological system in the soil (a wide range of fungi, bacteria, and creepy-crawlies), the organic gardener/farmer heads off many potential problems.

Any problems that crop up typically indicate an underlying health issue.

She emphasized that healthy plants resist disease, and that we can promote good root growth and beneficial microflora (and by doing so improve plant health) through providing compost and other organic amendments, by mulching, by reducing the amount of tillage, and by using cover crops.

Encouraging predator insects, parasitoids, and microbes as allies was also brought up. Relying on an ecological approach of planting flowers that are attractive to these beneficial organisms was part of the biological approach of disease prevention. Some diseases are in the wind and can’t really be intercepted or diverted, but others are spread through the feeding of insects, kind of like the way mosquitoes spread disease from one animal to another. The “beneficials” help by attacking the disease-spreading insects.

When I spoke with Dr. Little later in the day, when we were touring the campus farm, she emphasized the “right plant in the right place” approach to plant health in a great example: She said that she had seen lone tomato plants out in the full sun, with good mulch around them, well-fertilized and mulched, and they were completely unblemished – no signs of disease anywhere – when other tomato plants in the area were definitely ailing.

It was great that she chose Tomato as her example, because that seems to be the garden vegetable that is most affected by disease, in a way that causes the most distress to the gardener, in Georgia. Usually, when someone asks me about disease in the garden, we end up talking about tomatoes.

I left the workshop feeling extra-motivated to keep emphasizing the importance of all the little steps – using compost, paying attention to plant varieties and their disease resistance, making sure there is adequate sunlight for the plant, and using mulches and cover crops.

All in all, it was a great day.

Gardens and Talks

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This week I spent a couple of hours at a community garden in Smyrna, and it was mostly doing very well. It was great to see so many little gardens, and to meet more people who are focused on growing good food!

However, the garden was definitely having a pest problem. I have never seen so many beetles-per-square-inch before; these are kudzu bugs, and they were all over the pole beans:

So far, there is no good, established control method for these beetles, since they are new to the United States. Scuttlebutt has it that some entomologists at UGA are looking into the effectiveness of a parasitic wasp, but that’s really all I’ve heard so far. It is likely, though, that if next year gardeners grow their beans under row covers, they will be able to avoid (or at least delay) such dramatic infestation.

The garden’s tomato plants also had a problem, and I’m pretty sure it is Septoria leaf spot. The good news is that most of the garden beds already have produced a lot of tomatoes for the gardeners, so they have enjoyed a good harvest up to now.

The garden/farm where I volunteer on Saturdays has the same disease problem, and I’m guessing that it’s only a matter of time before the leaf spot hits my garden, too. Disease has been a huge problem for gardens all over the area this year. Gardeners who are not all that concerned about using organic methods have been keeping the manufacturer of Daconyl (a fungicide) in business this year, and the rest of us are muddling through as best we can.

I pulled out the last of my Cherokee Purple plants yesterday, but I have several other tomato plants still producing, so I’m not totally heartbroken. Joe says that the Tomato Man’s Amish tomatoes taste better, which means we still have what Joe thinks of as a “highly desirable” variety providing tomatoes for us.

Later today I’ll get to visit another community garden, this one out in the north-east corner of the county, and I will be talking some about getting ready for planting fall veggies and about pest and disease problems.

On the evening of July 31, I’m scheduled to talk at the county Extension office about getting ready for the fall veggie garden. Anyone who wants to come should call the office to sign up (770-528-4070; or email uge1067@uga.edu).

Bad News Bugs

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Just before I left town for another trip to Oklahoma, I saw three adults of the squash vine borer flitting among my plants, and I smashed two Mexican bean beetles in the bush beans. It looks as though the pests are going to be as early as the veggies have been! These are two pests that typically cause a lot of damage in my garden, and I know that my zucchini-days, especially, are numbered.

Also before I left town, I pulled up two tomato plants that were not thriving. The two were both Rutgers, which is normally my emergency backup, never-fail variety. Apparently, this gardening year is going to throw one curve after another at the veggie gardeners! When I pulled up the two plants, there didn’t seem to be anything overtly wrong. The vascular system looked clean (not gunked up with fungus) and the roots were un-knotted (no root knot nematodes); the roots were not vigorous, though, and the plants weren’t growing well. Since I don’t know yet what went wrong, I planted sunflowers in the spaces those plants were pulled from.

I got back home on Tuesday evening and didn’t have chance to do much more than take a quick look around the garden. Everything looked basically fine. But when I went around on Wednesday to check things out more closely, I saw that one tomato plant had been attacked by a pest:

The gaping holes and some black frass (poop) that had fallen onto some lower leaves were a huge give-away that the pest is one or more caterpillars, but I didn’t see any at first. When I leaned across to the next plant, though, I found one:


This guy is very bad news. He/she is an armyworm, and like the squash vine borer and the Mexican bean beetles, this pest has made an early appearance. My copy of the book The Organic Gardener’s Handbook of Natural Insect and Disease Control contains this somewhat alarming sentence about these caterpillars:

Larvae can consume whole plants in 1 night.

Needless to say, I have a date with a little sprayer full of Bt (the bottle I have is called Thuricide), the organic-approved pest control substance for caterpillars.

Even worse, when I was looking at the tomato-neighbor to the damaged plant, the plant on which I found the armyworm, I found some of these brown lesions on the lower leaves:


It’s a little faint in the photo, but the ringed brown spot indicates a disease called Early Blight, which means that this particular plant is a goner. Several leaves had similar lesions. After verifying the disease with my handbook (hoping that my first guess was wrong), I got out a pair of pruners and a big garbage bag so I could get this plant out of the garden.

The plant was big, and it already had nice big tomatoes on it – making the loss especially annoying – and it had to be cut up to be removed from the cage. Cutting through the stems was a revelation! The insides of all the stems were already completely brown, and the lower stem was mushy inside.

I haven’t decided yet what to plant in the space from which the diseased plant was removed. It shouldn’t be another tomato or tomato-family relative, but that leaves a lot of options open.

Happily, the biggest problem some of my plants have is that they are so overloaded with pretty flowers that they are falling over.  Bee balm always reminds me of fireworks, but my husband thinks they look like Sideshow Bob, from The Simpsons.

Tomato Disease: Bacterial Speck

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Yesterday, I went to look at a friend’s tomato plants, which were doing poorly. A quick inspection showed that, whatever the plants were suffering from, it wasn’t one of the fungal “wilt” diseases, and it wasn’t Early Blight (I recognize those on sight), so we wrapped a leaf in a damp paper towel for me to bring home for research.

I used Cornell’s Vegetable MD Online pages for tomato diseases to figure out the problem, which seems to be Bacterial Speck. The black dots were small, numerous, and ringed with yellow. In addition, one characteristic of this disease is that it thrives in cool, wet weather, which is exactly what we had for most of the early part of this year’s growing season, in April, May, and the first week of June.

It’s hot now, but my friend’s plants are in bad shape. One plant has lost nearly all of its leaves, some plants have several leaves that are completely wilted, and all the plants have spots on all of their leaves.

The several websites that I eventually read agree that the most common way a garden becomes infected with this disease is through infected seeds or transplants. I started from seed most of the tomato plants that my friend is growing, but my garden is not infected, which means that the disease is unlikely to have come from the Cherokee Purple, Arkansas Traveler, Rutgers, Yellow Marble, or Amish tomatoes that I gave her.

I did grow one variety for her that I did not keep any plants of for myself; it was the variety Black Seaman. She also brought in at least one other tomato plant from another source. Either one of these could have been the source of infection (and I plan to burn that packet of Black Seaman seeds, just in case…), but for now, the biggest question is whether any of her plants will survive.

The remedy mentioned on most websites I visited was spraying with a copper-based fungicide: either a Bordeaux mixture or a copper-maneb spray. However, research from western North Carolina suggests that some strains of the bacteria that causes speck (Pseudomonas syringae pv. tomato) have developed resistance to copper sprays. I am hoping that the strain in my friend’s garden is not among them.

Ways to limit the spread of this disease were mentioned in several online sources:

1. practicing clean cultivation (removing and disposing of plant debris–continually)
2. keeping tomato leaves dry
3. using mulch to avoid spread by splashing in heavy rains
4. choosing disease-free seeds and transplants (though this, obviously, is tough)
5. making sure plants are far enough apart that they get good air circulation and that one infected plant has a lessened chance of infecting all the others through splashing