This Terrible Weather.
In case you stepped outside on Tuesday (which I certainly tried to avoid), the ice rain probably kept you slipping and sliding. Add in the wind and hail, and making it to class was just pure misery.
Well it turns out this weather isn’t real great for plants either. Who knew?
As I told you a couple weeks back in my piece about starting seeds, I am working on an urban garden at the Pyle Center (on the rooftop and in the courtyard) for my F.H. King internship. I also told you (as I’m sure you remember) that we began a whole variety of plants indoors on March 18th.
Well, a month has gone by and the time has come for step 2 of the seed starting process for many of our plants: hardening them off.
I think it is safe to say that the weather has not been particularly cooperative. But somehow, our cute little seedlings, literally coated in ice on Tuesday night, have survived.
Hardening off is a vital step to the indoor, seed starting process. Hardening off is the time between indoor growth and transplanting, when you acclimate your plants to outdoor temperatures and conditions.
Obviously, then, as you slowly allow your seedlings to become accustomed to strong sunlight, less-frequent watering and cool nights, day 3 of your hardening off process should probably not include 8 hours in a hail storm. I learned something on that Tuesday, although conditions were far from desirable, plants can survive a multitude of conditions and are extremely resilient.
But I’ll spare you the details of our good fortune once the ice was scraped off each leaf, and instead tell you the ideal conditions and steps to follow in the hardening off process.
1. Know the hardiness of your seedlings. Lettuces, onions, leeks and brassica (broccoli, cauliflower, brussel sprouts, kale, cabbage, kohlrabi) are much more hardy an can handle temperatures in the 40s. (This is likely why our poor ice-covered seedlings survived, they were all brassica, leeks and lettuces). Peppers, basil, peppers, cucumbers and squash are considered tender and prefer temperatures above 60 degrees for hardening off. It is important to remember and listen to the advice that hardy plants can handle light frosts while tender plants cannot. Do not harden tender plants off too early!
2. Use a cold frame to protect seedlings from strong wind and creatures. If you google cold frames, you will see a lot of very official, mini greenhouse looking things with glass lids and strong walls. Again, these are used in an ideal world. You open and close during the day to gradually acclimate your seedlings without having to transport flats back and forth.
But, we built a lid-less cold frame out of large cinder blocks, stacked three layers high. It worked for Linnzi (the garden afficionado I’m working under) last year and is certainly working this year as well. My mom has been starting tomato plants inside for decades and we live on a windy hill. She just sets them on the side of the porch so they have some protection from the wind; they’ve also always been fine.
Sometimes going fancy with garden gear (such as a cold frame) is fun, but if you’re poor and trying your hand at gardening for the first time, feel free to be inventive. Like I said, plants are resilient.
3. Harden off gradually. Start with a mild day and leave the plants out for three or four hours. Increase the seedlings’ time outside for about a week, so eventually they are out in the elements for a full 12-hour day before being left out overnight. Typically 7 to 10 days is enough time to prepare your seedlings for the lower temperatures of night. Gradually reduce frequency of watering as well.
4. Watch the weather! It may have been 55 degrees and sunny today, but that tells you nothing about the possible low temperature at night. It is Wisconsin afterall, the land of eternal winter… Seedlings should stay outside overnight a few more days before being transplanted into the garden. So be sure to keep an eye on the evening temperatures. If temperatures are set to drop below 30 and your seedlings are in a cold frame, close it. If they are in a self-made, lid-less cold frame like ours, throw a large blanket over for insulation. If they are just sitting outside, bring them indoors.
I cannot stress the importance of hardening off seedlings as well as watching the weather predictions. It is so easy to rush the garden process. Especially when you live in a state where spring and summer often take their time arriving.
“It’s April, it’s warm sometimes, I want to play in the dirt and make things grow!” Yes, I know, these thoughts run through my mind as well, but rushing the process and not paying attention to nature will just leave you with a bunch of dead or stunted plants, and no one wants that.