As the days start to get shorter and cooler, homeowners start to wind down their gardening for the year. While you can still enjoy harvests and floral blooms extending into the autumn, you won't usually expect to enjoy either benefit if you plant seeds when the first frosts are fast approaching.

Turnips are an exception to the rule. The vegetable grows best in cool conditions, and its rapid development allows you to harvest before winter arrives.

While turnips are perhaps best known for their bulbs, which can be added to stews and other recipes, many people also grow them for their foliage. You can cut turnip greens from the plants multiple times before the growing season is through, enjoying them raw or roasted.

Turnips are most commonly grown as annuals. They can be planted in either spring, late summer, or early autumn. The gardening company Bonnie Plants says the latter two seasons are more advantageous, since unexpected hot days in the spring can result in greens with a more bitter taste. The plants will also start producing flowers and seeds instead of new foliage once temperatures climb in the summer.

When planting turnips, look for an area with full sunlight. They can also tolerate partial shade. The Cornell University Cooperative Extension warns that while turnips are somewhat hardy, they will also grow more slowly and have poorer flavor if they are grown in less advantageous conditions.

The soil should be well-drained and amended with organic matter. It also needs to be loosened to a depth of 12 to 15 inches to allow for the development of roots, meaning raised beds can be particularly useful. Turnips prefer acidic or neutral soil, with pH levels going as low as 6.0, but can also tolerate slightly alkaline soil.

Turnips won't transplant well, so seeds should be set directly in the soil. The Old Farmer's Almanac says seeds should be scattered and covered with a thin layer of soil, no more than half an inch deep.

Seeds will usually germinate within a week of planting. Once the seedlings reach a height of four inches, they should be thinned so they are four to six inches apart. If you are growing turnips for their greens instead of their bulbs, you can reduce the spacing to two to three inches, or even skip the thinning step altogether.

These early thinnings can be eaten instead of thrown away. Marie Iannotti, writing for the home design site The Spruce, says turnip greens will continue to grow as long as the bulb is not damaged. The greens can be harvested whenever they reach a height of four inches.

It's possible to benefit from continuous harvests, especially if temperatures remain moderate into the early weeks of winter. The Cornell University Cooperative Extension recommends planting turnips every two to three weeks to have an ongoing supply of bulbs and greens.

Turnips require fairly minimal maintenance. The Old Farmer's Almanac says the soil should be moistened with an inch of water per week to keep the root system healthy. Bonnie Plants says older, yellowing leaves should be removed to encourage the growth of new foliage. Beyond that, you simply need to keep the garden bed mulched and free of weeds.

Unfortunately, turnips are also susceptible to several diseases and pests. These include aphids, clubroot, flea beetles, powdery mildew, scab, and turnip mosaic virus.

Turnips are cole crops, related to vegetables such as broccoli, cabbage, and mustard greens. Iannotti says you can limit the risk of disease by rotating planting locations, making sure not to plant any cole crops in the same location two years in a row. This period should be extended to six years to minimize the chances of clubroot.

Pests can usually be deterred with row covers that keep the insects away from the leaves. The Cornell University Cooperative Extension says cardboard collars around the plants are also useful for deterring cutworms.

A hard frost will damage a turnip's roots and kill the plant. However, a light frost is useful for improving its flavor. Iannotti says turnip bulbs insulated by a layer of mulch can be harvested into the winter.

Bulbs should be about two to three inches across for the best taste. Older bulbs will have more of a pithy texture, but can still be mashed for use in recipes or softened up by cooking in soups or stews. Bulbs can also be stored for several months in a cool, dark location such as a refrigerator or root cellar.

Turnip greens are best harvested when nighttime temperatures have started to drop into the 40s. Bonnie Plants says leaves should ideally be harvested within a few days of the day you intend to use them, and can be removed in large amounts using a sharp knife.

It's possible to enjoy both the greens and a bulb harvest. After doing a few pickings of leaves early on, leave the remaining foliage in place to help direct energy to the roots. The bulb can then be harvested once there is a greater risk of a hard frost.