Photo by Helin Loik-Tomson - Getty Images
Spring Gardening
As we shake off another Wisconsin winter, most gardeners can’t wait to start playing in the dirt. While spring is too early to plant crops like tomatoes and peppers, other plants such as lettuce, kale, spinach and broccoli thrive during the cooler months of April and May.
Mark Jorgensen, who co-owns Plant Land (6204 S. Howell Ave.) with his sister, Karen Matt, sells nine varieties of “cut and come again” leafy lettuce varieties such as romaine that can be harvested repeatedly before the summer heat sets in. He says lettuce can be planted during April and can handle a frost of 30 degrees.
Spinach can be direct seeded into the ground during April and grows according to the weather. Peas, carrots, kale and chard varieties can also be planted by seed during mid-April.
Cruciferous vegetables such as broccoli, cauliflower, kohlrabi, cabbage and Brussel sprouts also do well during cooler weather. Jorgensen sells these plants already “hardened off” or transitioned from an indoor growing environment to the outdoors, by mid-April. He recommends a hardening off period of about four days outdoors for cruciferous plants started from seeds.
Unpredictable weather can still bring a late spring frost; if this occurs after planting, cruciferous crops can be covered with bed sheets or frost blankets.
When planting lettuce during early spring, full sun exposure is best. Most varieties Jorgensen sells are ready to cut for the first time 45 days after transplant, under optimal weather conditions. “But if you want to try to get a second cutting during mid to late May, lettuce does better in filtered light or partial shade.” Cut the leaves from lettuce plants one to two inches from the ground, rather than cutting the entire head or pulling the plant out of the ground, to yield three to four crops, or cuttings, from each plant.
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“But after about a week of 80 degrees, they’re done. I try to get the lettuces outside by April,” Jorgensen advises.
Once the summer heat kicks in, lettuce, spinach and broccoli can bolt, or quickly go to seed, leading to a bitter flavor that makes the plant unpalatable. “Planting lettuce under a tree will still provide some light yet keep it cooler, offering more cuttings.”
Kale and Swiss chard need full sun. Once kale and chards are well established, they can be harvested until the first killing frost in fall. Remove only the desired number of leaves and leave the rest of the plant intact, rather than cutting the entire plant, to keep it growing through fall.
Building Plant Resiliency
Photo by McManigal Photography Richfield
Plant Land Entrance
Plant Land
Jorgensen observes that many home gardeners make the mistake of overwatering their plants and “killing them with kindness.”
“I tell people to put your finger into the ground down to your first knuckle. If it’s dry that far down, you need to water—especially lettuce. Lettuce doesn’t like it soaking wet all the time, but if you let it dry out, that will also cause bolting. Broccoli will also bolt if it’s not kept moist enough.”
While climate change has affected traditional growing and harvesting times, Wisconsin is still considered a Zone 5. Yet we have microclimates that can also affect garden plants during the wild weather swings of early spring.
“When you hear ‘it’s cooler near the lake,’ remember that it gets warmer a few miles west of the beach,” Jorgensen says. “When you get to 27th Street (from Lake Michigan), you’re not near the lake anymore; you’re in a different zone that’s warmer in summer and cooler in winter. Just those few miles make a big difference.”
It’s tempting to baby tender young transplants, but they’re more resilient than we think. “After the first 10 days the plants are in the ground, you want to let the plant take care of itself, to a point. If you water too often, the roots don’t have to search for moisture and will stay near the surface. Then if you’re away from the garden for a weekend, you might not have plants when you return because the root system won’t support the plant. You want the roots to grow down to search for moisture. Making them work for it helps them become well established.”
