Drastic weather shifts add challenge to growing from seeds

When I looked out the window early Saturday morning, a light dusting of snow covered the ground. While it melted by mid-day, it was a reminder of just how tenuous the arrival of spring can be in March and April.

It’s tempting to succumb to optimism, to jump full bore into the changing of the seasons. A day after that token snowfall, I was standing on the open deck cooking steaks. Never mind that it was 35 degrees outside when I fired up the grill. It seemed like time to come out of dietary hibernation.

A similar dilemma confronts Kansas vegetable gardeners this time of year. The tease of a few springlike days, the aroma of warming soil and our eagerness to come out of winter hiding can dupe us into thinking we can start planting with abandon. The fact is that winter is still lurking, reluctant to release its grip on our climate.

I can think of no stronger lesson on this point than the hard freezes we had in April last year. Not only was the fruit crop done in, but folks who jumped the gun on tomatoes and other warm-weather transplants had to start over from scratch.

In a yo-yo climate like ours, where warm days alternate with cool ones, timing and the varieties we select are extremely important. We need to remember that the vegetables we put in the ground in late March and early April, either by seed or transplant, will probably endure fluctuations of temperature ranging from the 30s, perhaps even wind chills in the 20s, up to the high 80s before harvest in June.

In more even and moderate climates, gardeners don’t have to worry about such things. We are still in the USDA’s Zone 5, but folks in Zones 6 and 7 can start planting earlier with greater confidence that the growing cycle can run its course before actual hot weather sets in.

It’s no accident that the vegetables we traditionally plant in the early season in Kansas have shorter germination-to-harvest times. Lettuce and spinach, depending on the varieties, are typically 45- to 55-day crops. Cole crops, which are best grown from transplants, generally need at least 55 days from seed to harvest.

These vegetables also present a special challenge because they do their growing above ground and are easily damaged by wind, particularly when the plants are young and struggling to anchor their root systems. In the case of lettuce, whose roots are particularly delicate, a wind barrier may be necessary, depending on the location of the garden.

The best lettuce in this climate, bar none, is Black-Seeded Simpson, which can be seeded early and has some heat-tolerance. A variation called Simpson Elite supposedly will grow a month or so longer without bolting or turning bitter. Seed for Simpson lettuce is widely available. Green Ice, a Batavian lettuce, also boasts heat resistance. My favorite red lettuce, New Red Fire, is reasonably heat-tolerant and slow to bolt.

For spinach, Space, which has relatively flat, spoon-shaped leaves, has a longer growing season in this climate. I also like it because the leaves are easy to clean.

In broccoli, Packman, a short-season variety, is probably the best bet for the Kansas climate. Stay away from Waltham, which is popular with seed and plant vendors but requires a three-month season of cold weather to reach its potential.

Selecting varieties that are appropriate for this climate simply requires a careful reading of the available information, whether it’s on a seed packet or in a catalog, followed by a dose of common sense.