And we’ve begun the process of hardening off! We’ll have much more to say about this topic, as hardening off is a critical step for the indoor seed grower, but let’s first discuss some of our background philosophy.
The average grower that intends to transplant around last frost does not need to be hardening off this early. In our situation, though, we have a heated greenhouse that can ward off frosts and we’d like to get our plants growing out in the sun as soon as possible. So, that allows us to start this process fairly early, typically 4-8 weeks to last frost.
Figuring out when to do this in the early season like this is tricky business! We don’t know what the weather’s going to do and we’ve still got snow in this week’s forecast! But, what we’re looking at are trends where overnight temperatures are expected to be in the mid-to-high 20’s Fahrenheit.
Any heat we apply to our greenhouse has a cost. We’ve done a lot of experimentation with our greenhouse heating and we know that it’s cheaper for us to heat our greenhouse at a certain point than it is to run our grow lights. Below mid 20’s and it’s cheaper for us to keep our plants indoors under grow lights! In the mid-to-high 20’s (or above) and it’s cheaper for us to have them in the greenhouse.
So, we’re sort of looking for that “magic point” where the scale tips towards it being more economical for our plants to be in the heated greenhouse. From what we see at this point, that scale looks like it’ll tip for us possibly as early as this weekend. That could absolutely change, we’re not wizards here! We watch the weather like a hawk during this time! And we’ll bring our plants in or out based on conditions.
Unfortunately, these equations are not universal advice we can give anyone. You have to find those tipping points for your gear and situation by measuring your heating or lighting inputs and calculating the operating costs. There’s just no other way to figure it out and if you’re wrong, it can really hit your pocket book!
You also might notice that we’re exclusively hardening off “cold climate” veggies like celery and onions at this point. Our warm loving plants, like peppers and tomatoes, will definitely be waiting for warmer days for us to begin this process. But, right now, we’ve got a brisk 40 degrees and these particular plants will be just fine at these temperatures. We’ll be getting into these nuances much more deeply, it’s part of what we’re known for.
So, an exciting evolution of our indoor from seed garden! Much more to come on this stuff, but we try to keep it digestible for you!
