Two people have told me recently that it is best to keep tomatoes from getting rained on, in the Lower Mainland, to prevent disease. Is this true? What is the disease, and when during the life of the tomato plant is this most critical?
The worst for us is called late blight and as the name would imply, it usually happens late in the season when the plants are full of fruit and it's a heart breaker. Individual plants will die within days and it spreads rapidly. We have had some success removing all the fruit and culling any that seem even the tiniest bit affected, but only in the range of 30% saved (for immediate canning). Along with the covering, you should also do only drip or other low level watering, so as not to wet the foliage. Ralph
Search Phytophthora infestans. It will probably get worse soon, a new strain has been found in Europe, enabling the old one to cross with a new partner to produce more virulent ones. Already it seems it may be best to consider the tomato plant a greenhouse crop here, it really likes more heat than we have (and late blight can be quite a spoiler for us).
