It is March 1st, so it is time to start thinking about starting your tomatoes indoors. Below I outline my tips for starting tomatoes in my climate, zone 6B in northeast Oregon.
Tip 1: Don’t start too early! They will catch up.
In northeast Oregon zone 6B, it isn’t really safe to transplant your tomatoes outside until June. The earlier you start your plants, the more of your house they will take over before they can go outside. Also, the earlier you start them, the deeper the hole and the more time it will take to transplant them outside.
I shoot for a plan that is about 8 inches tall and no more than 12 inches. However, my friends at Val’s Veggies in Medical Springs plant them much smaller and they catch up easily. Seeing how Val’s does it has made me want to plant smaller and smaller plants. I think smaller starts are generally more healthy because they have less time to develop problems or get leggy.
I think planting any time in March is safe for a healthy crop. Maybe try planting some tomatoes early and some later in March this year and see what works for you. Notice if the starts catch up with each other in size before planting and what happens with transplants too.
Tip 2: One seed per pot
I’m all about reducing complexity and work down the road. If you can carefully put one seed per pot or planting tray cell, it is a lot easier than trying to carefully disentangle tiny seedlings or thinning them later.
Tip 3: Big, deep pots
I like to start my tomatoes in large, deep tubes because I don’t have time to transplant 400 plants up from small trays. If you do start in small trays, make sure you transplant up to larger pots once they get bigger. Remember there should be at least the same depth for roots as you have for the shoot above ground. What I mean is you don’t want a two foot tall plant in a shallow pot. It is better to have a pot that is too big than too small.
Tip 4: Lots of light
Many people ask, “why are my tomatoes so spindly?” Answer: Not enough light! If your plants are consistently “leggy” your window isn’t doing the trick and you need a grow light.
Tip 5: Watch for disease & pests
We have trouble with mice getting into our greenhouse at night and mowing down young tomatoes and peppers. We set traps to reduce loss. Slugs will do the same thing, so consider leaving Sluggo pellets around your plants.
If you’re a smoker, do not touch your tomato plants without gloves. Tobacco mosaic virus can easily spread from your hands to tomatoes and it is bad. Give your plants the best start.
Tip 6: Whack ’em back
If your tomatoes get really healthy, and tall with thick stems, you can whack them back without worry. If they are making a jungle in your house or just getting too darn tall, it is important to prune them for a better transplant. Again, you want a 50/50 root to shoot ratio. If anything, you should have more/deeper roots than you have shoots above ground.
Remember to pluck off flowers and fruit before you transplant them. Both just waste your plant’s energy at the beginning of the season when they should be putting on vegetation rather than fruits and flowers.
Tip 7: Don’t transplant too early!
At our farm, we’ve had frost as late as Father’s Day often. If you plant before Father’s Day in June, be vigilant. You can use “Walls o’ Water” or remay/cloche to keep the frost off, but they only provide so much frost protection.
At our farm, we plant tomatoes inside the hoop house about May 15th and plant outside after Father’s Day. A lot of folks in our valley say, “wait to plant until the snow is off Mount Emily.” So you can try that if you want.
Keep an eye on the 7-day weather forecast to look for a good time to plant. I know the weather report for our farm is usually correct when it comes to precipitation, but wrong on the forecasted low temperatures. I usually just subtract 9 degrees to the forecast for a more accurate estimate.
Again, if your plants are huge but you don’t think the conditions are right for transplanting, just prune them back and wait.
Those are my tips! Thank you for reading.
Your grateful farmer,