Introduction: Growing Tomatoes in the Pacific Northwest USA
I grew the best tomatoes in the impossible conditions of the of the cold wet area north of Seattle. While it was not a high elevation I think it could be done. I used to start the seedlings indoors, in February or March, under florescent grow lamps. They do grow tall and lanky, so I added another pot on top of the first one by splitting it down the side and tape together. Then filled them up as far as I could. Also using tree seedling pots is a good way to fit more under the lamps. But the more roots the plants have when transplanted the faster they will grow.
Cold weather tomato seeds like Stupice or Siberian
3x3 or 2x2 inch plastic pots [half should be split to wrap around the long stem]
Planting soil that drains well. [peat moss and compost?]
Rock phosphate and Bone meal [dig into garden beds]
Florescent plant lights.
Clear plastic sheet roll.
ABS tubing [to hold up the plastic sheets]
Old boards with holes drilled to hold the tubing in a crossing arch. [optional]
Old cement reinforcement wire is good for holding up the plants.
In April I transplanted them out in deep holes so there was only a little bit of leaves above the soil. And covered them with plastic to hold in the heat.
Doing this gave the plants a huge amount of roots because the plants grow roots out of the stems. So they became quite large very fast. It was worth all the extra work. No one else I know was getting tomatoes until a month or more later. As soon as the tomatoes are big enough, stop watering [start of august], so that all the energy of the plant goes into fruit production and sweetening the fruit. The way I prepared the soil really helped produce a lot of tomatoes also; they need a lot of phosphate. I dug-in rock phosphate and bone meal the spring before. Too much nitrogen will make the plants grow but they will not produce tomatoes early enough. It is possible to make compost with more phosphate and potassium than normal using restaurant vegetable scraps and sea weed. Don't use much manure, too much nitrogen makes the leaves grow but not the fruit. I tried that once and ended up with a huge amount of tiny green tomatoes. And vertualy no ripe ones. Stupice and Siberian are the 60 day varieties that I used because they were genetically selected to grow in cold climates in Europe. Don't even bother with large tomato varieties. Small tomatoes are so much sweeter.
Step 2: July
When the tomatoes develop cut back on watering to help them ripen.