One of the simplest ways to keep the garden producing at full volume is to make sure it is full of growing crops at all times. After you harvest the first of the summer crops, you will often have time to plant more of them (and should), but you should also start thinking about the fall and winter garden. Winter crops need to do most of their growth before cold weather and short days arrive and slow them down. The almost mature plants will then continue to grow slowly (if the winter is mild), or sit in the garden in an edible state until harvested (if the winter is cold).
Planning the winter garden starts with choosing suitable hardy crops, which would include Asian Greens, Beet, Broccoli, Brussels Sprout, Cabbage, Carrot, Cauliflower, Celery, Chard, Collards, Chicory, Kale, Kohlrabi, Leek, Lettuce, Parsnip, Rutabaga, Spinach, Turnip and more. You also have to choose the right varieties for winter growing, as there can be considerable variation within a crop. You want cultivars bred to tolerate cold temperatures and short day length.
The right time to start your winter crops depends upon where you live, but generally you can start planting the slower maturing crops, such as leeks, parsnips, celery and Brussel sprouts in mid-summer (July). Transplants of broccoli and cabbage can be started in August for planting in the garden through September. Quicker maturing vegetables, such as turnips and kohlrabi may be planted through mid-October. Generally if you’re your garden isn’t super fertile it’s best to start all of these earlier rather than later. If plants are too small when winter arrives they will just sit in the garden looking pathetic and embarrassing. When spring comes they will resume growing for a week or two and then bolt.
When you open up large areas of bed by harvesting, it makes sense to use the first of them for direct sown crops such as carrot or parsnip that can’t be grown from transplants. At this time of year the bare soil of a seed bed will dry out very quickly, so it’s a good idea to cover it with shade cloth. This keeps it cooler and moister and reduces the need for watering. I like to go even further and cover slow germinating crops like carrot or parsnip with a sheet of cardboard or plywood until just before I expect germination to occur (this also keeps weeds down). Cool weather crops often don’t germinate well at high temperatures, so if a period of cool weather is forecast I try and take advantage of it and get sowing.
Where possible I like to grow winter crops as transplants, as I can get them growing while the garden beds are still occupied; no need to wait for vacant space. You can start the transplants in the greenhouse if it’s not too hot (some cool weather crops won’t germinate if the temperature is too high), but it is usually warm enough to start them outside too. You can simply grow them in flats on a table covered in bird netting, though they will need frequent watering, as containers dry out rapidly. You could also use a specially designated nursery bed, which is simply an area of bed with good soil and covered with bird netting.
For those of us in the milder parts of the country the winter garden is often just as important as the summer garden and this is a crucial time of year. If you miss the window for getting your plants established, you won’t have a winter garden.