You do not have to be an avid weather observer to know that frost is imminent and may have already taken place at some of the higher altitudes. I made it to a point this week to complete the harvest of what was left of our sore crops before any chance of frost. That meant picking the last bush beans, cucumbers, okra, eggplant, tomatoes, peppers, melons, squash and sweet potatoes. Even without exposure to frost, the quality of most of these vegetables decreases with repeated exposure to cold, but above freezing, temperatures. In agricultural circles, this is typically referred to as cooling damage. It is not surprising that the vegetables listed as sensitive to cool weather are all of tropical or subtropical origin.
Two vegetables that are often confused with being frost tolerant are pumpkin and winter pumpkin. Of course, most everyone recognizes that frost kills the vines of these crops, but the fruit always looks like it withstood the cold and is even picturesque when coated with the thin ice-cold glaze. Although there will be some problems if they are harvested and cooked immediately after exposure to frost, they will soften and decay quickly when stored. Cooked pumpkins and winter squash can be mashed and eaten, used in pie or bread recipes or frozen for consumption this winter.
The lawn full of leaves? Before you put the fallen foliage up and kick it to the curb, consider making your own compost pile. Garden Journal columnist Ron Kujawski tells how to make a simple trash can.
While pumpkins, squash and the other mentioned crops are not hardy, there are still many crops that can withstand frost. Those that can withstand temperatures in the range of 28 – 32 F include beets, broccoli, cabbage, cauliflower, carrots, celeriac, celery, chard, parsnips and radishes. Among the vegetables that can withstand temperatures colder than 28 F are kohlrabi, turnips, rutabaga and many leafy vegetables such as arugula, lettuce, spinach and kale. The harvest season for all these hardy vegetables can be extended well into the winter, especially if they are given some protection. For example. a thick layer of straw over root vegetables will prevent the soil from freezing, making it easy to dig in carrots, turnips, rutabaga and parsnips. The season for green vegetables can be extended by covering them with row covers or cloches or creating so-called low tunnels from metal hangers or 1/2-inch PVC pipes and clear plastic. I have been able to harvest kale through an entire winter using the low tunnel approach.
One of the hardy vegetables mentioned above is celeriac, a relative of celery but grown for its large swollen root instead of its leaf stalks. It is a vegetable that apparently does not get much attention and I must admit that I have only planted it a few times without much success. My lack of success is largely due to a lack of attention to detail in its growing demands. Celeriac is not difficult to grow, but it does take a long time to ripen. Ideally, the plants should be started indoors from seed around mid to late March. The seedlings are transplanted to the garden in late May or early June.
Growth is sluggish. It is the swollen root that is sought, but the development of the root takes a long time to increase in size and this is where patience is essential. I think in the past I just gave in, dug up the root too soon and was disappointed by its small size. This year I have been waiting and am now being rewarded with baseball-sized roots. Since celeriac is hardy, I only harvest as needed and will leave the remaining plants in the ground well into the fall and can even cover them with straw. As with many root crops, the taste of celeriac improves with exposure to frost. Harvested roots can be stored in a cool, dark but airy place.
The first celeriac roots I harvested this year were cut into thin slices and added to a tossed salad. The taste of celeriac has been described as being related to the taste of mild celery. My next dish with celeriac will be a stew or soup.
Growing celeriac has taught me to be patient and pay attention to detail.
Here are other tasks that require at least some attention to detail:
- Finish peeling dry beans, then store the beans in masonry jars along with a desiccant pack or oxygen absorber. However, reserve about 1/4 pound of each bean variety to use as seed for next year’s planting.
- You don’t have to worry about trees and shrubs that might be blooming out of season right now. Several people have told me that their forsythia is in bloom. It is not unusual when we have a prolonged warm period in the fall. There is no damage, but do not expect these plants to bloom next spring as it is too late to form new flower buds.
- Place herbs in pot under a fluorescent light if they become long-legged. Usually, natural light from a window during the fall and winter is not enough to keep these sun-loving plants happy. (I know how they feel.) An exception is mint. It can withstand the diminished light of winter.
- Use several different products in an alternating way if you use deterrents to deter deer from eating on trees and shrubs. If only one product is applied to plants, the deer will eventually get used to it.