4 Methods for Providing a Continuous Supply
As the days grow longer each spring, temperatures increase and the workload usually does, too. But once the midsummer sun has reached its zenith, the crops you plant thereafter will be growing and maturing in gradually shortening days and cooling weather. Because crop life cycles are governed above all by light and temperature, it's important to plan your plantings so crops are ready to harvest when you need them, right from the very earliest date possible into the very end of the season. Follow the principles and practices of succession planting laid out below to achieve an optimal outcome.
Advantages of Succession Planting
Putting the principles of succession planting into practice takes some of the guesswork out of planning and results in a steadier supply of produce — ready for harvest over the longest possible period. Succession planting gives you the ability to:
- Maximize space
- Extend the harvest window
- Maintain a continuous supply
- Optimize quality and yield
4 Succession-Planting Strategies
Several proven strategies can be implemented, starting around the time of the summer solstice, to help ensure a continuous supply of fresh produce from late summer into fall and winter:
- Start planting varieties that are adapted to mature in cooler temperatures.
- Plant several varieties of the same crop that have different days to maturity.
- Incrementally time successive plantings more closely together, as they will be maturing more slowly into the fall.
- Adopt season-extension technology for crops that mature into the fall, to cover and hold them in the field without damage from early winter weather.
Read on to learn more about each of these strategies.
1 • Variety Selection by Season
Many seed crops are bred and selected for various traits, including heat and cold tolerance as well as their ability to thrive under lower or higher light conditions. Within a particular crop, some varieties perform better in cool weather and some in warm weather, some under increasing daylength, some at peak daylight, and others under decreasing daylength. If you grow only one variety of a crop, you may find that it falls short of its potential at some point or another during the season.
By growing several varieties, you can span a longer season and still offer consistently high quality. Depending on the crop, our planting/harvesting programs recommend sowing different varieties at different times of the year, and/or sowing multiple varieties with different days-to-maturity (DTM) to spread the harvest across time from a single planting.
Succession-planting systems can become increasingly more refined, complex, and productive as the grower gains experience. The intervals can be tweaked by factoring in regional or individual farm-record data, and by adopting more innovative and advanced techniques, such as season extension methods.
2 • Johnny's Succession-Planting Interval Charts
Johnny's Research & Trialing team has created a set of charts that show the recommended intervals between sowings for crops that are especially well-suited to repeated plantings of the same crop.
Download our calculator (XLSX) …
Visit PlantMaps for average frost date in your area…
The timing between successive plantings on these charts relates to the average days to maturity (DTM) for the crop or variety listed. Keep in mind that the intervals between plantings shown here are based on standard growing practices — in reality, optimal planting intervals are also contingent upon local frost dates; growing conditions; and methods of planting, growing, and harvesting.
Planting tips and notes are provided, and the charts can also help you decide which crops to grow concurrently.
To forecast the dates of your successive plantings, try our Succession-Planting Calculator. You can use this calculator to determine dates for sequential, staggered plantings, whether counting forward from last regional frost date in spring, or backwards from first fall frost date.
You also can combine indoor seed-starting to produce transplants with direct-seeding to effectively succession plant. For example, you can start transplants of crops you normally direct-seed, such as arugula, cilantro, cucumbers, parsley, spinach, squash, and sunflowers. When you plant them outside, direct-seed some of the crop at the same time. The transplanted crop will be ready for harvest first, and the direct-seeded crop will mature a few weeks later.
3 • Succession-Planting & Harvesting Programs
Planting programs differ from interval succession planting in that they generally involve planting several crop varieties that have varying days to maturity, as well as planting different varieties depending upon the season, to produce a continuous supply. As with interval succession planting, many growers apply season-extension methods as an integral part of their planting programs.
Visit the Planting Program section of the Grower's Library to learn more about the details of implementing a successful program.
4 • Season-Extension Technology
Finally, protected cropping bears mention, as it can help you expand the limits of your growing season significantly, allowing for production earlier in spring, later into fall and winter and, for some growers, year-round production.
Use several types of season-extension structures to tailor the protection to the crop. The possibilities are numerous. Here are just a few examples:
- Plant low-growing crops such as greens in Quick Hoops™ low tunnels, or cover them with floating row cover or Quick Hoops to hold them in the field when cold weather arrives.
- Cover peppers and eggplants with row cover to help them survive the first frost or two. There is frequently a return of mild weather following the first frost, that can help some tender crops survive into that period.
- Plant a late crop of determinate tomatoes in a hoophouse, or keep a main season planting of indeterminate hoophouse tomatoes productive after field crops have slowed down.
- Plant cold-loving crops in early autumn in a hoophouse or caterpillar tunnel to harvest all winter.
- Overwinter some crops under Quick Hoops to give them an early start the following spring.
Putting It All Together
Succession planting may seem complicated at first, but with practice you'll get the swing of it. Start with a few main crops and project your harvest dates, then use these four strategies to find opportunities to extend the harvest. Do the same thing with additional crops next season. Try a few new varieties from the Planting Programs to see how they produce for you. Experiment with high tunnels and low tunnels.
Keep track of the details, then analyze the results. You'll soon be on your way to creating a succession-planting plan that provides for abundance and quality — and strong sales — over the longest possible season.
More Succession-Planting Resources
Planting Intervals for VEGETABLES • Chart
Planting Intervals for HERBS • Chart
Planting Intervals for FLOWERS • Chart
Succession-Planting CALCULATOR • XLS
Johnny's Planting Programs • Charts
Scheduling Vegetable Plantings for Continuous Harvest • ATTRA Sustainable Agriculture • PDF