The cool, damp weather we've had in the past week and the mild temperatures now in the forecast are perfect growing conditions for cole crops. This is the category of vegetables that includes broccoli, cauliflower, cabbage and kohlrabi. In this climate, these vegetables need to get the majority of their growing done before the end of May.
Cole crops can be ruined by too much heat. Even if the plants continue to thrive, the flavor of the harvest can be destroyed. In addition, broccoli will bolt, or go to flower; and cabbage, kohlrabi and cauliflower turn rubbery.
Because time is of the essence, we're generally better off here to grow these crops from transplants than to seed them directly into the ground, which will lengthen the growing cycle. An exception to this guideline is broccoli raab, or broccoli rapini, which is a non-heading, more pungently flavored Italian broccoli, which can be ready to harvest in fewer than 50 days.
The fact that our gardens will start to bake in June means that we need to pay close attention to the growing times of the varieties of cole crops we plant. A suspect broccoli choice for the spring garden in Kansas is Waltham 29. It has been around awhile and gets a lot of buzz because the plants are large and produce a lot of side shoots -- but it takes nearly three months to grow to harvest. That means that the plants will mature in hot weather and will be more likely to bolt early. Packman, which is widely available at area greenhouses, is a better choice in this climate.
Similarly, Kansas gardeners want to steer clear of long-growing cabbages, such as Danish Ballhead, which reportedly is a good storage cabbage but is best left to gardeners in milder climates. Golden Acre is a better choice for northeast Kansas.
Graffiti, a purple cauliflower, also has attracted considerable attention because it holds its color during cooking, and blanching is not a concern. (Most white cauliflower is now bred to be self-blanching, meaning the leaves will grow up around the head to protect them from sunlight. However, some varieties of white cauliflower need to have their leaves tied up.) The drawback to Graffiti is that it needs to be in the ground about 75 days, so it might have trouble in our gardens unless it gets an early start in a cold frame.
As an alternative, Snow Crown is a popular variety that matures in about 55 days. Although it doesn't have the spectacular appearance of Graffiti, it is considered to be self-blanching and has some disease resistance.
One of the most overlooked cole crops is kohlrabi, which is a bulbous vegetable that grows above ground with leaves that stick out like spokes from the bulb. Kohlrabi is mild-flavored and can be stored in the crisper drawer more than a month. When it appears in grocery stores, it sometimes is coated with wax. That's a sure sign that the vegetable is not fresh, and the flavor will be nothing like the kohlrabi that comes out of the garden.
The discerning reader will notice that I left brussels sprouts off the list of cole crops, and that's because in this climate they really do require an earlier start than most gardeners are willing to give. The flavor of home grown brussels sprouts -- at least those grown in cool weather -- is exceptional. But that's just the problem. Brussels sprouts take about three months to mature, and growth slows dramatically when temperatures settle into the mid-70s.
One of the great advantages to growing your own cole crops is that they taste so much better when they are freshly harvested. But there's another, more practical benefit, namely that insects are not an issue in cool-weather gardening. Three months from now, when the squash bugs and bean beetles have settled in, that will seem really significant.