Posts Tagged ‘late blight’
My artichoke plants are a semi-satisfying success in my small kitchen garden this year. I started several plants from seed indoors in February, and transplanted four into my garden in June. These plants clearly have no intention of making chokes this year, so I’ll devise cold frames or other cover to protect them from deep-freezing during the winter. Perhaps next year I’ll harvest some artichokes.
The growing season had already been tough on my small kitchen garden, and then I really let it go. I spent a week at the annual symposium of the Garden Writers Association, and left my garden to fend for itself. Things were pretty sketchy when I left, but they were downright distressing when I returned.
When I left, I had been collecting tomatoes but things had just gotten started. Plants were topping out at seven feet, and I’d harvested about three gallons of fruit. While there appeared to be many more fruits setting, some type of infection was spreading among the plants. Lesions that looked like late blight had started low on stems and leaves and they were working their way up the plants.
Small Kitchen Garden on the Brink
When I left, climbing beans were just starting to put out flowers. There were three distinct clusters of bean vines growing among the tomatoes. A too-small trellis in an ornamental bed supported too many healthy-looking, crowded bean plants,
Finding a fence panel out of position makes me a little uneasy: how long has it been this way? What classes of rodents have noticed? Is anyone now inside my kitchen garden? What might already be dying because critters have come-and-gone through this huge opening in the garden’s defenses?
When I left, a stand of sweet corn held the promise of, perhaps, two dozen ears for meals—assuming anyone harvested them as they became ripe.
When I left, my cucumber plants formed a bush of healthy green on my deck and they were flowering like nobody’s business.
When I left, my bush wax bean plants were bereft of mature beans, but there were many young beans starting, and plenty of bean flowers were open.
When I left, my winter squashes were putting out blossoms every morning. I hand pollinate my winter squash, so I dreaded missing so many days; no one in my family would be willing to pollinate the squash flowers.
The Sad State of My Small Kitchen Garden
The photos show and explain what I found when I returned to my small kitchen garden. For the most part, the garden’s situation is grim. There are some bright spots, and I’m confident things would be little different had I stayed home… sometimes the elements simply don’t cooperate with a kitchen gardener. It makes me unhappy for a bit, but eventually I shrug and look ahead to next season.
When I returned from the Garden Writers Association conference, my wife asked, “Where are your bean plants?” She had, apparently, looked for them so she could harvest beans, but she hadn’t found them. Sure enough, plenty of beans had matured beyond tender while I was away; I sorted through them to find young beans my family would be willing to eat… but it gets worse: When several of my tomato seedlings had failed in late summer, I had planted climbing beans in their places. The bean plants were healthy and poised to bloom when I left, but two plants were wilting badly when I returned. Those particular bean plants have since died.
Sure, most of my corn plants tipped during a big storm, but kitchen gardeners lament that corn always falls over. My sadness related to corn is that no one harvested any while I was away. There are, perhaps, two dozen ears that should have been eaten but that will, at best, be old and tough if I harvest them now.
I pick tomatoes when they just start to blush. These tomatoes are nearly fully-ripe. I found many overly-ripe tomatoes in my small kitchen garden after my weeklong trip… the green shoulders and cracks illustrate why I pick tomatoes at the first sign of pink and let them ripen indoors.
As sad as I was to find nearly-ripe tomatoes on my plants, this discovery made me much sadder: there’s no question my tomatoes have late blight; all my tomatoes. Many look healthy, but the plants they’re on are in horrible shape. My tomato harvest is done for this season—far too early.
The cucumbers also misbehaved in my absence. In fairness, had I stayed home they’d have been no different. Several oddly-shaped cucumbers developed, but none are compelling enough that I’d harvest and eat them. For this, I’ll concede I didn’t give them the best chance to succeed. I planted too many seeds in deck planters and they performed as if stressed. I’ll grow cukes in planters again, but I’ll set far fewer seeds per gallon than I did this season.
There is a bright spot in my small kitchen garden. Actually, it’s all over the garden: My winter squashes are in decent shape. On the left: a small neck pumpkin. In the center, two small butternut squashes next to a huge butternut; the rear-most squash (only partially visible) is at least five times the size of the one in front of it. On the right: a Blue Hubbard squash that doesn’t seem interested in becoming a giant. Still, it’s great to have several Blue Hubbards that have survived past the typical onslaught of Squash Vine Borers… I hope they survive this more than double the average rainfall for August and September.
This may be the champion squash in my small kitchen garden. It’s a neck pumpkin hanging on what I usually use as a pea trellis. The squash was about 22 inches long in this photo, and it has grown about three inches longer since I took the shot. I’ve seen neck pumpkins weighing more than 25 pounds!
When I first posted about these unusual tomatoes, I called them “Italian” tomatoes. Since then, other people have suggested they are “Dutch” tomatoes. I had not heard the term “paste tomato” by 2008, but I understand now that the category of paste tomatoes includes those that are mostly meat with relatively little liquid. These are paste tomatoes. What’s more they have a striking resemblance to the Andes tomato I found in an online seed catalog. My neighbor has been growing them for years.
I started writing Your Small Kitchen Garden in August of 2008, and that emboldened me to visit a neighbor whose garden I had eyed from the road for more than a decade. I wrote about that neighbor’s garden in this blog on September 15, 2008 in a post titled A Large Kitchen Garden.
I very much enjoyed meeting these neighbors, and was fascinated with the unusual chili-pepper-shaped tomatoes they were growing. I was moved a bit when they handed me two of the curious tomatoes insisting that I should save the seeds and grow them in my own small kitchen garden in 2009.
Tomato Luck in my Small Kitchen Garden
I needn’t remind anyone what a miserable growing season 2009 presented in the northeastern and the southwestern United States. I got lucky: while late blight destroyed tomato patches all over Pennsylvania, I harvested several bushels of tomatoes before lesions appeared on my plants.
Among the tomatoes I harvested were dozens and dozens of those chili-pepper-shaped treats grown from seeds I saved from my neighbor’s gift. I raved about those tomatoes in my blog. They are awesome-sweet and flavorful, and I served many of them in my favorite tomato salad. As well, I canned gallons of sauce, diced tomatoes, and tomato halves. After all that, I also dried tomatoes using my toaster oven’s dehydrate setting.
I saved seeds. In fact, I collected seeds from, perhaps, a third of the uninfected chili-pepper-shaped tomatoes I harvested in 2009.
Growing Pains for Kitchen Gardeners
By the time blight hit my small kitchen garden, I had seen its effects on many other local gardens. Driving past my neighbor’s yard nearly daily, I watch his garden evolve through tilling and early growth and then go right into death throws. I never saw tomato plants there rise above surrounding vegetation and I wondered: did he lose his entire crop? Worse: did this miserable growing season break his streak of growing those lovely chili-pepper-shaped tomatoes? I wondered whether he had harvested seed… or whether he had seed left over from 2008 that he might try again in 2010.
My neighbor grew lima beans two years ago, but told stories of a giant variety of lima beans that they used to grow until the crop failed on year. I’ve seen giant lima bean seeds in catalogs, so I’m going to track some down and do some seed-sharing.
So, while preparing seeds to mail to readers who have participated in my free seeds giveaway, I thought I’d take a packet of seeds to my neighbor. I figured he might be glad to have fresh ones from 2009 so he could grow more of those cool tomatoes.
It had been a year and a half, but it took only a moment for my neighbors to remember me. We talked a bit about what a horrible season 2009 had been for kitchen gardeners, and I learned that their garden had suffered a lot from the constant rain. Turns out, being an in-ground bed, their garden doesn’t drain, so it does best during very dry years when everyone else must add water to get decent results.
It wasn’t clear whether my neighbors were seedless, but they seemed genuinely grateful for the seeds, and quite happy to talk about their garden and the coming season. He will be 82 years old next month, and still he’s figuring to manage his large garden bed.
I agreed to track down seeds for super giant lima beans and visit again before it’s too late to plant them. Apparently, my neighbors grew such lima beans years ago but things didn’t work out one season and they’ve lost the strain.
In any case, as I’m sure most gardeners would attest: talk with gardeners about gardening, and you’re making friends. That’s how it felt yesterday, and I’m looking forward to another visit.
If you visit Your Small Kitchen Garden blog often, you’ve probably seen this photo of diseased tomatoes on the vine in my garden. Home growers were particularly distressed by tomato diseases, but some commercial growers also lost crops.
I’ve written much in Your Small Kitchen Garden about the woes of home tomato growers in 2009. As you might expect, some commercial operations also suffered this year. While most apply chemicals to stave off late blight and bacterial infections, some don’t. What’s more, conditions were so bad this season that even chemically-treated crops might not have escaped disease.
Our local paper ran an article yesterday about a crop-sharing group that lost money because of the tough tomato-growing weather. It’s fascinating to see the figures the commercial growers cite in the article. For example, the growers expected to harvest 31 tons of tomatoes per acre; instead they reaped only 19.42 tons per acre.
Another telling statistic: Because of low temperatures and excess moisture, it took 42 days for tomato plants to grow significantly after planting compared to seven days last year, and only four days in 2007! Everyone in the eastern united states seems to have had this type of weather, but apparently your plants might have faired better if you planted them later in the season.
Buying shares in crops can be an economical way to get fresh produce for non-growers… though some crop shares pay out only in cash (as the ones in the article seem to). Crop shares are also a terrific way for farmers to spread risk for years when things don’t go quite right. This was one of those years.
The article is an interesting read. Please check it out: Tomato gamble withers on vine
Late blight infections in 2009 spread all over the eastern United States, wiping out many small kitchen garden tomato crops. Late blight can express itself as brown discoloration on tomatoes – green or ripe.
As the plants fade in your small kitchen garden, the temptation grows to get out there and clean things up. If the plants aren’t going to produce more, why keep them around? The question became more complicated for many this year when late blight destroyed tomato plants all over the north eastern United States.
I posted about late blight in an article titled Tomato Strife in Small Kitchen Gardens Everywhere, and subsequent conversations got me curious about late blight. I did some research and learned stuff about late blight that every tomato- and potato-grower should know.
Late Blight is Mold
For years I’ve heard late blight referred to as fungus, but last month at a tweet-up with a group of gardening enthusiasts in upstate NY, Bridget McManus (@b_mcmanus on Twitter) put me onto an article that identifies late blight as mold. So, late blight is mold, but it’s susceptible to chemicals that kill funguses.
Pretty much any place a late blight mold spore sticks to living tomato tissue, a lesion will emerge in four to six days. By this time, chances are spores have infected other nearby plants and tomatoes.
There’s vaguely good news about late blight: most late blight in the United States is of one strain or another so in a particular infection, every mold spore is genetically identical. These identical molds can reproduce only asexually resulting in spores that can’t survive beyond about four hours without a living host… unless they’re in the soil. To make durable spores, mold must breed sexually—that is, it must breed with a strain of the mold that is genetically different from itself.
To gardeners, asexual late blight means infections die out along with the plants on which they live.
Small Kitchen Garden Late Blight Management
If late blight can survive only on a living host, why do people fuss about the importance of removing blighted plants from your garden… and not adding the plants to your compost? There are several reasons:
- Active late blight on any plant can rapidly spread to other plants. In fact, if you see lesions on a leaf, stem, or fruit, there’s a reasonable chance that blight spores have already spread to other leaves, stems, and fruits.
- A plant may not show signs of infection for four days after becoming infected.
- A single lesion can release hundreds of thousands of spores every day, each of which can cause a new lesion.
- Spores, while not hardy, can survive for about four hours without a host—or several weeks if they get mixed into the soil. That gives them plenty of time to ride the wind to neighbors’ plants or to wild plants that might provide a nurturing environment.
Late blight shows as brown splotches on stems and leaves, and rapidly spreads over the entire plant, eventually killing it. In the lower-right background of this photo, there is a seriously-infected green tomato… actually quite brown at this point in its demise.
So, your attitude toward blighted plants should be about containment: By the time you recognize late blight in your small kitchen garden, it may be too late to save your crops. However, if you remove the plants and bury them six inches underground… or bag them and put them out with your trash, you may slow the spread and spare other gardens from the ugly disease.
The risk of composting is that the compost heap may provide ideal conditions to keep asexually-produced spores alive far longer than they’d live out in the air. Worse: if you also compost susceptible roots or tubers, spores may infect them and winter over.
Put Your Small Kitchen Garden to Bed
With rain and wind, late blight spores eventually spread over the entire surface of a plant, making it look mummified. Amazingly, while every scrap of green on this plant was overwhelmed by late blight, the actual fruit ripened and dried without growing lesions.
Late blight dies along with the plants it’s infecting. So, if you have blighted tomato plants in your garden when killing frost hits, your blight problem may be past. I say **may be** because you might also have potatoes in your garden… or there may be wild plants nearby that can host late blight mold spores.
So, if your tomatoes had late blight, pull the plants out, bag them, and put them out with the trash… or dig a deep hole for them well away from your garden, and buy them under at least six inches of soil. Dig your potatoes… make sure you don’t miss any. The one you leave behind could be the vector for next year’s late blight infection.
Aside from these activities, don’t work the soil in your infected garden bed; once you’ve cleared the plants away, give remaining late blight spores several weeks to die out: don’t cover old, dead or dying plants with mulch (grass clippings and fallen leaves count as mulch). In fact, I’d leave the garden bed exposed to the elements through the winter and plan on adding amendments at the beginning of the next growing season.
Sad News for Prevention
When last I wrote about late blight, I explained steps you can take to reduce the chances of your plants becoming infected. Sadly, in a wet growing season, those steps may be only marginally effective. The sad truth is, the only reliable way to prevent infections is to treat your plants against fungus throughout the growing season.
Naturally, there are chemical, non-organic sprays that are highly successful. I’ve spoken with several farmers at the local farmers’ market whose sentiment is, “I didn’t have any problems with blight this year because I used chemicals.”
Apparently, the most effective organic preventatives are sprays containing copper… which can build up to toxic levels in the soil. Alternatively, spraying foliage with compost teas has proven somewhat effective according to the National Sustainable Agriculture Information Service.
So, the answer to the question, What can I do now to prevent late blight infection next season? is, very little:
- Hope that your late blight has lived asexually
- Remove all plant material that could host late blight in and around your garden (potatoes, tomatoes, eggplants, peppers, and nightshades must go)
- Leave the soil undisturbed and uncovered for two or three weeks before amending it or mulching it
Next year, you’re not likely to see late blight unless the weather treats you the same as it did this year. If you hate to gamble, you’ll have your best chance of success if you treat your plants regularly with antifungal spray that’s labeled as a late blight preventative. You need to decide what treatments are acceptable to you… and what level of loss you can tolerate should your garden disappoint.
Some information for this post came from the Cornell University Vegetable MD Online web site. It’s an awesome resource for kitchen gardeners.
Here are some other sources for information about late blight:
The Return of Late Blight (Cause of the Irish Potato Famine … – Late blight is infamous as the cause of the Irish Potato Famine, an unforgettable period of Irish history in which four consecutive years of potato crop failure in the mid-1800s left millions of people starving or dead.
Preventing late blight next season | Brownfield – Purdue University plant pathologist Dan Egel says steps can be taken now to prevent late blight from showing up again next spring in tomatoes and.
Genome Of Irish Potato Famine Pathogen Decoded – A potato plant infected with Phytophthora infestans. A large international research team has decoded the genome of the notorious organism that triggered the Irish potato famine in the mid-19th century and now threatens this season’s …
Late Blight — Irish Potato Famine Fungus — Attacks U.S. Northeast … – Leaf lesions due to late blight. Home gardeners beware: This year, late blight — a destructive infectious disease that caused the Irish potato famine in the 1840s — is killing tomato and potato plants in gardens and on commercial farms …
A cluster of tomatoes illustrates the ugly progression of late blight through my small kitchen garden. I’m losing about a bushel of tomatoes to the horrible disease.
It’s not news to anyone who owns a small kitchen garden: This has been a challenging year for gardeners in North America. I’m sorry if this was your first year planting a kitchen garden; I hope the aggravation wasn’t enough to discourage you in coming years.
The south western United States experienced sustained heat and dryness; I heard complaints from gardeners that they couldn’t keep plants watered and cool enough to get decent harvests.
The Atlantic coast and clear out to the Midwest had crazy, sustained rains and cool temperatures. Especially in the north—from New York up into Canada, rain drowned the roots of vegetable plants, and the cool temperatures slowed growth.
Late Blight and Tomatoes
Perhaps worst of all this growing season: Late blight, the fungus that created the Irish potato famine in 1845, shipped along with tomato seedlings to big-box garden centers all over the eastern United States. Late blight thrives in the cool-wet, and for the most part, tomatoes didn’t have a chance.
I completely fell in love with these tomatoes in 2009. Shaped like peppers, they grow quite large. They are so devoid of moisture that they float in water where beefsteaks and other slicing tomatoes sink. They taste terrific. Sadly, the last twenty or so still in my garden are infected with late blight.
According to the Encyclopedia Britannica, late blight is an American export; someone accidentally introduced it to Ireland. I long ago learned that the late blight fungus is pretty much always on-hand, waiting for the right conditions to kick it into action. A gardener’s best defense against late blight is culture:
- Provide good drainage— If drainage is good, air movement around your plants’ roots is also good; and good for the plants..
- Minimize moisture— Water only as much as the plants need; I haven’t met a vegetable plant that wants its roots wet constantly.
- Control moisture— That is, focus watering on the soil near plants’ roots; don’t use sprinklers and spray nozzles that soak foliage with every watering.
- Don’t crowd plants— You can plant things closer than seed packages recommend and you’ll get great production… as long as everything else goes right. I understand the risks of crowding and I take the lumps when they come… but please choose a level of pain that’s acceptable to you. Crowding traps moisture, blocks air flow, and provides easy pathways for insects and diseases.
- Make sure air can circulate freely— If there’s a lot of air movement within your garden plot, plants will tolerate crowding better than they will in a well-sheltered area.
- Rotate crops— Don’t plant the same crop in the same area two years in a row. Ideally, figure a three- or four-year rotation; don’t repeat tomatoes in the same space for three or four years if you can avoid it.
- Follow a crop only with crops that aren’t closely-related— Tomatoes, potatoes, peppers, and eggplant are all related closely enough that if you plant one in a specific area this season, none should go in that area next season. Please check my small kitchen garden store for books that will guide you to responsible choices for next year’s crops.
- Prevent the spread of disease— Remove sick plants quickly. Bag them and toss them in the garbage, but don’t compost them.
- Plant seedlings grown locally— Best of all: learn to start your own plants from seeds about four-to-six weeks before you put them in your garden. If you prefer to leave that hassle to someone else, at least find a local nursery or garden store that starts its own seedlings. The farther you go for your live plants, the more opportunities the plants have to acquire unwanted pathogens.
I feel pretty confident in guessing that this bell pepper is inflicted with late blight. I had been anticipating a second wave of peppers to harvest in early autumn, but the very difficult growing season had other ideas.
I got very lucky this season:
- I started all my plants from seeds for the first time ever.
- The micro climate of central PA was cool but “wet enough” meaning we got rain when we needed it, but not to excess. I’m quite sure it was low temperatures that caused the most trouble.
- Despite heavy crowding, my plants showed no sign of stress until late August.
- By late August, I’d already harvested about 3 bushels of tomatoes
- Late blight spread very slowly in my garden; it seems to have missed the potatoes, though it seems to be damaging some of my peppers.
Despite the good luck, in just two weeks, my tomato plants have gone from late-season production of gorgeous fruits to overwhelming melt-down with nearly every fruit showing ugly brown lesions. I’m used to harvesting tomatoes up to the first frost, but this weekend I’ll be pulling all the plants and stuffing them into a plastic bag for garbage pickup.
Keep On Gardening
This was an unusual year! It is my first in fourteen seasons at this address where disease has taken hold… and some of those years were far wetter. My guess is that the temperature was the biggest villain in my garden’s problems; summer seemed to last about two weeks. Those weeks fell between three months of early spring and the sudden onset of autumn.
So, don’t be discouraged. Chances are, next season will be “normal…” and if not, perhaps the season after that will be.