Late Blight Resistance--Tomato Trials

Well, our tomato trials are about to begin. I have seeds for two of the varieties we are hoping will show resistance, and the rest have been ordered.

If you haven't been reading, scroll back a few posts for information on this awful tomato disease, and a link to photos of the nasty things it does to a tomato plant (See post "Have you seen this tomato disease?). Tomato late blight is the disease that caused the Irish potato blight, and a new strain of it has been destroying tomatoes in the Bay Area for the past 10 or 15 years. Some recent scouting around on the web that I did turned up reports that a few tomatoes might resist it, so we plan tto grow a bunch of them at City College of San Francisco this spring and try them out. We will have some extra, which will be available in the plant sale, which is traditionally the Thursday before Mother's day, in the day time. If you are interested in participating in the trial, you can come and purchase a few, or, you can just grow your own and send in some results at the end of the summer.

We will be growing: 'Legend' (medium-sized fruit, bred for resistance, but may not resist the strain we have, from Territorial Seed Co.), 'Koralik' (cherry-sized, from Territorial Seed Co.) 'Tommy Toe' (cherry tomato, from Totally Tomatoes), 'Juliet' (grape-shaped tomato, from Totally Tomatoes), 'Matt's Wild Cherry', from Seeds of Change), red currant (wild variety, tiny fruit, from Totally Tomatoes, I think, but available several places).

Only 'Legend' was bred intentionally for resistance, the other choices are just based on informal reports.

If you plan to do this, you have to grow a control too, just to be sure you actually have the disease. (The spores fly in the wind to land on your plants, rather than being in the soil.) So grow one or more of the possibly resistant varieties, and also grow one that would get it if the spores landed on it--most any other kind will do. I have used 'Celebrity', a short plant that is resistant to just about any other tomato disease, but gets late blight. Or you could just grow some 'Early Girl' or 'Stupice', both tall plants with medium small fruit, and good production and flavor.

Let me know if you are planning to run a trial. We need a few going in different places to see if results agree.

Comments

[Pam Peirce]

Sweetwater comes through again in 2011 with 'Vis Valley' tomato seedlings! One commenter above mentions saving its seeds. This is a good idea, since it's an open-pollinated variety so it should come true next year from saved seed. I have also grown 'Taxi', which does well in cooler locations as long as late blight is not a problem.

See my book Golden Gate Gardening for more on these and other varieties to try in Central California coastal and inland gardens and for information on saving tomato seeds.

[Donna]

Sweetwater Nursery in Sebastopol, CA has Visitacion Valley tomato plants available. I work at Whole Foods Market and purchase their organic tomatos, veggies and herbs to sell in my store and their products are phenomenal!

[Phyllis]

I found Vistacion Tomato seedlings at the Davis Food Co-op. Looking forward to seeing how it does.

[Tovar]

After searching the Internet extensively for seed this winter without a luck, in late June, I came across some Visitacion Valley seedlings from Sweetwater Organics at Empire Nursery (on Guerneville Rd, west of Santa Rosa). Alas, they were only 6" tall (as compared to the tomatoes i started from seed in January, a couple of which are now 6' tall). But i picked up one for a friend and another for myself. I'll learn how to save tomato seed in a way that retains its genetics and see how each does next year.

We picked up a several early tomatoes at the Kendall-Jackson Heirloom Tomato Plant Sale on May 2nd and the 'Taxi' has already made a cluster of tomatoes that are beginning to show color. (They are supposed to be bright yellow.) They hope to have Visitacion Valley next year. And Taxi might be another candidate for planting in the City if you're looking for a low acid tomato.

[soni]

Sweetwater has Visitation Valley again and Whole Food has the starts. I got a couple late starts when part of my was over infested with verticillium wilt. I took out two of my garden tomatoes cause if it, and bought the Visitation Valley as a patio tomato to make up for some of my garden tomato loss.

[S. Bardell]

I bought a Visitacion Valley seedling from Sweetwater Organics last year at one of the outdoor displays (can't recall if it was at Whole Foods or Rainbow) and saved seeds. I have one planted out (15-gal container) and perhaps a few others I didn't have space to plant out.

If it does well again this year, I will make an effort to save more seeds, though I do still have a few.

[pampeirce]

Hi Angela, I don't think anyone is offering 'Visitacion Valley' now. Some mailorder nursery was, for a while, and I, thinking they would continue to do so, foolishly didn't pay attention. Now I don't see it anywhere. But 'Stupice' is really good, so I suggest you try that.

[angela]

I am wondering if anyone knows where to find "Visitacion Valley" tomato seed or plants. I read it in the GGG and cannot find it anywhere. I am out in Dillon Beach and thought it would do well...any thoughts.