Many gardeners were obviously very disappointed, and some have decided never to grow tomatoes again. I think, however, that it is possible to minimize and even avoid damage by following a few basic steps in tomato growing. Since the spores of the tomato blight will certainly be around next year, it is very important that everyone follows these rules:
1. Spacing
Plant your tomato plants at least 2 feet apart to improve the air circulation around the plants so that they will dry out faster after rain or dewy nights.
2. Staking and Training
Place a study stake next to each plant, and tie the plant to the stake as it grows. Tomato cages make too dense plants, and are not recommended. Prune the plants, gradually removing the lower leaves as the plants grow and training the indeterminate varieties to two main stems, removing all side shoots that grow from the leaf folds.
3. Watering
When watering, never get any of the leaves wet, only the ground. Deep water as needed a couple of times a week, never do frequent shallow sprinkling.
4. Sanitation
If you see any signs of disease, immediately remove the affected plant parts and take them away from the garden. Do not place them in the compost bins, since the disease organisms may overwinter in the compost.
In my trials, I have found some tomato varieties to be more resistant to blight than others. Early Girl, Dona and OG50 are fairly resistant mid-sized tomatoes. Sun Gold is a cherry tomato which has also shown some resistance. All of these varieties do, however, succumb to the blight at some point, usually about 4-6 weeks after the first symptoms as compared to 2 weeks for the most susceptible varieties.
Despite the blight, we still had a very successful Tomato Taste-off on September 9th. Growers in Ballard and West Seattle had been spared from the blight, probably because of their proximity to the sea with the constant breeze which dries out the plants faster than inland. The event was held in connection with the Seattle Tilth Harvest Fiest, and almost 50 different varieties participated. This year's new surprises were Persimmon, Green Zebra and Evergreen. The last two are green when ripe, with a full, aromatic flavor.