Garden Variety: Extend the harvest season with succession planting
To make the most of garden space and extend the amount of time that vegetables are harvested from the garden, consider succession planting. Succession planting is a process that takes a little bit of planning, but most gardeners can easily incorporate it into their year-round planting routines once they understand how it works.
There are a few methods of succession planting that can be used on their own or in combination. As spring fades into summer and the time comes to plant warm-season crops, consider incorporating one or more methods.
The first method of succession planting is to plant in intervals. An example is planting a small patch of spinach every two weeks from the middle of March to the end of April. Then, each crop of spinach matures at a different time and can be harvested for about a six-week period if the weather cooperates. By contrast, if only one patch of spinach is planted, it matures all at once or over a period of a few days.
Another method of succession planting is to follow a cool-season crop with a warm-season one and vice versa. An example of this is to plant beans (warm-season crop) in May in the spot where radishes (cool-season crop) were harvested from a spring planting.
The third method of succession planting involves careful study of maturity dates (listed as “days to harvest” on the label) and planting multiple varieties with differing maturity dates around the same time. For example, sweet corn has maturity dates ranging from 60 to 100 days. A gardener could choose one variety with a quick maturity date (60-something days), another variety with a maturity date around 75 days, and a third variety with a late maturity date (90-something days). All three varieties are planted at the same time, but because they mature at different times, the harvest season is spread over a longer period than if only one variety were planted.
Squash, melons, corn and beans are good options for planting in two-week intervals. The best times for planting these species are early May to mid-June. All of these crops can also replace cool-season crops such as lettuce, spinach, peas and radishes that have been recently harvested.
Tomatoes, peppers and eggplant can also replace cool-season crops. Planting in intervals is generally unnecessary, though, since these crops tend to produce throughout the summer if weather conditions and fertility are right.
Sweet potatoes can replace early crops and be planted in intervals if desired. They are best planted from mid-May to the end of June. They might be an especially good selection to replace fall-planted garlic, which is typically harvested in June.
In August and September, cool-season crops can start replacing warm-season ones again, if the warm-season crops have finished producing.
Early-planted and maturing squash and green beans may be fading around this time and could leave open spots for fall crops of beets, broccoli, cabbage, cauliflower, carrots, kale, radishes, spinach and turnips. These fall crops can again be planted in two-week intervals with attention paid to maturity and frost dates. These can all withstand light frost.
If mulched properly, the root crops can stay in the ground until a hard freeze or possibly even through a few freezes.
Cover crops may also be used in the fall to restore fertility to the soil and provide organic matter for longer-term soil improvement.
— Jennifer Smith works in regulatory horticulture and has worked as a horticulturist for various government entities. She has experience in landscape design and maintenance and as an educator.