We started these from seed much too early we believe. They are now about 12" tall and remain under a grow light inside. At what temp will they be ok to place on our covered deck to wait for the proper time to plant in the grnd? We know if it will be freezing temps, then they need to come back in or protected. Regards, Ray
Polk County Oregon
Thank you for your tomato question, Ray. You are correct in saying you started them too early. The challenge isn't so much the ambient (atmospheric) temperature, but the temperature of the soil, which should be at least 70 degrees, as this Extension article cautions. Although the soil retains heat better than air, it can be July before the soil is that warm. So, I'm afraid you will have them as house guests for 3 months more. You can start to put them out during the day, but ambient temperatures should be above 60, so you'll have to bring them indoors at night for quite a while.
For next year's crop (or other vegetables you might want to plant this year), here's a link to an OSU publication that has a great chart on page 7 with starting and planting dates for each region in Oregon. It has lots of other valuable information for the home gardener, as well. Hope it's helpful. Good luck!
Thank you Kristena. We'll attempt to keep them upright and healthy.
You’re welcome, Ray. If you really get into this, you might want to acquire a greenhouse!