Growing Tomatoes in a Heated GH

[Hudson_WY]

This year we started our seeds the first week of February under grow lights. We plant them in 3/4" soil blocks so there is plenty of room on the germination pad. It is much easier to germinate them in the blocks!

Then we move them directly into 4" pots until they are ready for the GH. The seedlings out grew the grow lights in six weeks from planting so "ready or not" we opened our Heated GH on the 13th of March.

The outside temperatures varied from -5° to 39° F (and still do) so we set the inside GH min temp at 55° and the max temp at 85°. On a sunny day the inside GH temp can reach over a 100° even though it may only be 25° outside. The max temp is as important too! We have to shield the seedlings from the inlet louvers so they don't freeze when the fan system kicks on. I also plug the louver vents with insulation during the night to help save on energy costs.

We heat the GH with a 45,000 btu propane heater regulated on a thermostat. It only costs us about $150 a year from the middle of March through November to heat the GH depending on the cost of propane. Our GH is very efficient with our triple-wall polycarbonate and silicone sealed cracks.

It is always a concern if the seedlings will get enough sun planting them in the GH so early in the spring here in Wyoming. Some weeks we get very little if any sun. The middle of March seems to be the compromise time of year in order to economically heat the GH and keep the seedlings happy with enough sun.

Without a GH we couldn't even grow tomatoes here in Wyoming. We only have a 45 day growing season and are at risk for frost every month of the year! We are in Zone 3 but now that we heat our GH we can get even an earlier start and almost keep up with zones 7 & 8!