For an interesting and informative article on last summer's devastating Late Blight epidemic on most everyone's tomato crop check out:
http://www.cpbn.org/article/summer-without-tomatoes
Especially interesting was the finger-pointing at Bonnie plants, sold at WalMart and other big box stores!
Excellent info on Late Blight
Appreciate you sharing that link.
I hope growing my own seedlings will help.
I've always considered the Bonnie's product to be the best of the lot as far as plants that were available in the mass market retailers. I'm sure they had no intention of dropping this bomb on we home gardeners, but it happened.
As far as growing your own seedlings; I do grow my own in my greenhouse, and used the previous year's potatoes as seed crop, but it didn't help at all. Late blight is carried airborne and can travel miles. I'll confess that I stood there and said "what the **** is that stuff" until it was way too late. Actually, I now know that by the time you see the symptoms it's already too late unless you have access to commercial grower type chemicals.
jhwentworth: As the article said, using previous year's potatoes as seed is a big no-no, although I did the same thing! Yes, LB is carried airborne, but the only way it survives over the winter to begin with is in potatoes. Since LB doesn't survive in the soil or on dead leaves, etc. only in potatoes themselves, this year I'm starting with fresh seed potatoes, being sure to pull up any volunteer potatoes that sprout on their own.
Hopefully, we won't have an unusually wet summer and we'll all have great crops of tomatoes and potatoes! Good luck!
This message was edited Feb 14, 2010 10:30 AM
HoosierGreen: The potatoes I planted in 2009 were from 2008, when there wasn't a problem with LB. Folks have been saving seed potatoes for years, and most of the time it works out fine. I agree that this year it would be a poor choice.
Here's some info I got from our state university (UNH):
Potatoes:
The varieties Abnaki, Belchip, BelRus, Cheiftan, Chippewa, Hudson, Monona, Norchip, Russet Rural, Superior and Wauseon are described as moderately resistant.
Atlantic, Bake-King, Frito-Lay 657, Green Mountain, Katahdin, Russett Burbank, Snowden and Red Norland are considered slightly resistant.
Kennebec, Rosa and Sebago are considered highly susceptible.
Tomatoes:
In general, indeterminate cherry tomatoes are less susceptible than other varieties. This is because they keep on growing and often "outgrow" the disease once the environmental conditions become less conducive to the disease. While breeders are working to breed late blight tolerant large-fruited varieties, I'm not aware of any that have been released to date.
Interesting that there doesn't seem to be consensus on susceptible varieties; other sources have said that Kennebec had some resistance. There's a possible source for Defender potatoes in Maine, but it's not normally a retailer and may not want to get into that business.
In a conversation with our state (NH) cooperative extension service about LB the rep asked if I had LB last year. When I replied "yes", she said that if we have a wet spring/summer this year I was at high risk to have it again. LB spores can travel long distances and not everybody will clean up completely.
Let's just hope we have a normal-rainfall year.
I gave a vegetable gardening talk this week to a group of over 80 gardeners, ranging in age from young to old. I asked for a show of hands to see who had a bad year for tomatoes and/or potatoes. The ONLY person who had late tomatoes was the guy with a hoop house for his crop. Everyone else just moaned!
I've read about a great, semi-new, fungicide that can deal with LB, downy mildew, powdery mildew, Septoria, turf rust, and a multitude of other nasties. The trade name is Quadris, and the active ingredient is azoxystrobin. It's pretty low in toxicity for mammals, bees, earthworms, and insects, but you have to keep it out of lakes and rivers. You can buy it without a license and the worker safety precautions are reasonable. Sounds perfect, right? Checked with my local retailer and the smallest container is 1 gallon, at a cost of $483.50. Back to the drawing board.
I'm with you; "Let's hope we have a normal-rainfall year".
Holy $#@%&! $483.50 a gallon!!! It'd be cheaper to hire someone to spray your tomatoes!
Lucky you, girlgroupgirl! I'll have to try your regimen this summer. Thanks.
girlgroupgirl: Was LB prevalent in your area last year? In areas that were hard hit the steps you took wouldn't have made a big difference. LB is airborne and the spores can travel miles. The time from infection to destruction was maybe a week, and by the time you saw symptoms it was too late. I've had a garden for probably 30+ years, and I have never seen late blight. When it happens a little extra air space ain't going to get the job done.
Commercial growers have dealt with both early and late blight for years, this is just news to most home gardeners. The commercial guys use heavy-duty fungicides to control this stuff.
http://www.whatsonmyfood.org/food.jsp?food=TO
Viva la homegrown!
My neighbor bought tomato starts from a local seller, as he always does. I started mine from seeds. He grew beefsteaks. I grew cherries. His tomatoes were completely wiped out in about two days from blight. He got no ripe tomatoes. Mine eventually started to get blight, which reduced the production, but I got cherry tomatoes until the end of the season. One plant kept on going longer than any of the others--this was Matt's Wild Tomato, which is a different species and not very susceptible to blight. I'll definitely be growing a lot of cherries again this summer.
I also tried using a straw mulch on a few beefsteaks, because it was described somewhere as helping to prevent the spread of blight due to splashback. Those plants didn't get blight until the very end of the season, but because of the mulch, I never realized when they needed water, so they were scrawny and a waste of time. I will never use a straw mulch again.
A final note here on the search for LB-resistant varieties. I found a seed potato grower in Maine that raises Defender potatoes. Defenders are supposed to be highly LB resistant. We exchanged emails and he offered to send me a "sampler" of Defender at no charge if I would agree to provide feedback on the results, especially if there was LB in my area this year. Yesterday the post office delivered a box with 16 pounds of seed potatoes. I'll store them in a cold spot until a week before it's time to plant. One of the better gifts I've received, and it isn't even Christmas. I'll pick up some Chieftains for my red potato.
For tomatoes I've gone with Legend and Stupice, and will start my transplants in a couple weeks.
Wow. This is sure a great opportunity for you, jwentworth. To be part of the trials, AND to benefit this year is a real treat. You'll have to let everyone know how it goes. Good luck.
"To be part of the trials"
Yeah, I think I'm there to provide the "idiot-proof" testing.
Hey, it's to your advantage to be their "idiot"! It also speaks to your initiative to contact the grower to begin with. Who would have thunk?