May 3rd, 2023
It may feel like the winter weather will never let up, but planting season is just around the corner! And whether you have a green thumb or have never grown a thing in your life, this is the perfect year to gear up your garden with some new gardening know-hows.
Sweet Potatoes
My holiday go-to vegetable is the sweet potato. Not only is it versatile and easy to prepare in the kitchen, but the stems are a good alternative to spinach, too, thanks to their similar textures and nutrients. But how in the free-floating snowflakes can they be grown in colder, often wetter environments like that of Michigan or Wisconsin? It’s easy; just follow the tips below and you’ll be all set!
- Know your taters. Beauregard is one of the most common species of sweet potato grown here, known for its quick maturing rate (90 days) and its higher cold tolerance. However, the Jewel, Garnet, Georgia Jet, and Covington varieties are also popular among Northern gardeners. When choosing what kind to purchase, consider what size, shape, and flavor you’d like, as well as how drought/water/cold-resistant they are. Note that it may take up to six months for the plant to produce.
- Know your soil. While these tubers aren’t super picky about the ground they’re planted in, like most potatoes, they prefer sandy, rich, and well-drained soil. This enables their roots to spread out with little difficulty and without encountering large pockets of moisture that can lead to rot. Only water every other day unless it’s especially hot out and the plants are showing signs of yellowing or wilting. Reduce watering near the end of your variety’s days to maturity to prevent the skins from cracking.
- Plant at the right opportunity. May through early June (or three weeks after the last frost) is the best time to put the sweet potatoes or sweet potato slips into the ground. Preferably, soil temperature should remain no colder than 55°F at night. This also plays a factor in harvesting as you’ll want to dig them up before the first frost in autumn.
- Lay plastic down. Technically, this step is optional. However, it keeps the weeds down and the warmth in the ground. Place a sheet of two-sided billboard tarp or landscape plastic down white first and cut slits where the potato bushes will sprout. Silage tarp plastic found on farms works great, too. These can be purchased at feed mills or anywhere you buy garden plastics.
- Harvest. Pitchforks and shovels both function well to dig up tubers, if you don’t plan on letting the roots continue to grow next year. However, you’ll want to do no more than loosen the soil if you desire otherwise. Note: Sweet potatoes require curing under very particular circumstances to be stored for long periods of time after harvest, so do some research and plan in advance how you’ll go about doing this. I’ll be cooking and canning my own. You can collect the leaves for eating once or twice a week by trimming a small portion of the bush, tossing out the stems to be composted. Always leave a clump of healthy green material behind.
Growing Ideas
- Humble bundle. Sweet potatoes can be quite happy in a raised garden bed, a plastic bin, or a big pot. Be sure to provide about a 12” diameter, 12” deep area for them to grow. The tubers won’t be quite as big as if they’re in the ground, but you’ll still have something delicious to take home at the end of the day (or inside, should it get chilly early in the year). To ensure they have more essential nutrients available to them, add compost, chicken manure, and rice husks to your soil mixture (available in hardware and gardening stores).
- Mound baby. All potatoes appreciate a 10” mound of soil heaped over their row in the garden, even these guys. This is because the tubers push upward through the soil when they begin to crowd (leaving them exposed) and because the stems tend to grow fairly tall (resulting in poor support). You can even add a trellis for hand-weaving the green material into manageable clumps.
—Grace Desotell, Gardening Editor