Updated: Mar 12
Looking to grow your own greens (almost) year-round here in New Hampshire? Kale, the darling of health nuts, is also one of the hardiest greens and will happily provide you with salad most of the year. Here’s what you need to know:
One secret to growing year-round kale is to keep a KALEndar (yes, I did just write that… please keep reading anyway!). The key to success with any greens is to make successive plantings throughout the growing season, so it’s important to mark planting dates on your calendar or set reminders on your phone.
The photo above shows succession planting. I interplanted later-season greens to mature as this early kale died back. The photo to the right shows the kale that overwintered in my garden last year, which turned into a beautiful kale forest by mid summer. The photo below shows kale going to flower. I harvested seeds from my kale for the first time this year. Updates on that project next spring.
I always start my spring and summer kale inside in February and March AND outside in March, April, and May to ensure I will have plants early and often. I start my fall and winter crop in the late summer (keeping it out of the high noon sun) so I will have established plants before the sunlight wanes.
I started this kale in late summer for fall and winter harvest. You can see all the grass is dead from the heat and drought, but the I moved the kale into the shade during the hottest times of the day to protect it from the sun.
The other secret to growing year-round kale is to use a cold frame, hoop house, or greenhouse. While a greenhouse would almost definitely give you a year-round harvest, greenhouses are definitely more of a time and money investment. If you are up for the challenge, here are some greenhouses made of recycled windows to inspire you. We are hoping to build one of these at some point.
Hoops are a much easier option and hoop houses (aka low or high tunnels), while less solid than greenhouses, will give you pretty decent insulation and frost protection. They are usually constructed of metal or PVC frames and covered with either plastic or some kind of plexiglass or poly-material. Cold frames, which are usually built of wood, are another option. If you’d like to get all dorky about the different kinds of hoops, houses, frames, and tunnels, here’s a good article, but really anything that protects your garden from frost and gives them a bit of insulation is good.In the past, we have used simple low tunnels with a double layer of plastic in the community garden, and had pretty good results. We didn’t harvest anything in the deep winter (mostly because we didn’t get over there), but we did have kale through Thanksgiving and a few plants overwintered and were producing in early March.
This year my husband built a wood cold frame for my new raised garden bed. For the moment, it is covered with the same old battered piece of plastic, but we intend to upgrade to something more solid and sustainable soon. Since this garden is right next to my house, instead of down the street, I am hoping for a close to year-round supply of kale. We will keep the cover on the kale when it is cold, placing an old pot of hot water in the frame on very cold nights. When there is a warm day or a steady rain, we will uncover the garden.
I hope you will consider creating a KALEndar and join the year-round vegetable gardening community by constructing a winter kale garden. Please post any other methods you use to extend your growing season here in New England.