Year-Round Harvest- Planning your garden
A common question I hear is, "What do I plant, when?" Timing is a cornerstone in the garden. For experienced gardeners this becomes intuitive, but when you are first embarking it can be a steep learning curve. The same is true when one moves to a new gardening zone.
To make it simple in my mind, I lump annual veggies into two main groups: warm season and cool season. Most climate zones experience their warm season in the summer months and the cool season in the shoulder seasons of fall and spring. The exceptions to this are northern latitudes and mountain/coastal zones where cool season veggies can often be grown in the summer.
Warm season includes tomatoes, peppers, eggplants, melons, cucumbers, squash, corn, basil, sunflowrs and beans. Essentially anything that will die from frost is in this category.
Cool season includes most greens like brassicas and lettuce, broccoli, cabbage, roots like carrots, turnips and beets, peas, onions and many herbs.
It can be helpful to look to the USDA Plant Hardiness Zone Map to learn what your minimum average winter temperatures are where you live. Using this information you can guage what will survive in your winter garden. Our farm is in zone 9 with average minimum temps of 20-30 F. From experience I know I can grow most leafy and heading cool season crops, as well as roots, through the winter. Covering the plants with frost cover improves results and protects them from those very cold swings into the low 20s F.
When is your first and last frost date?
This will inform when you plant your summer crops. It will also tell you how many days approx you have to grow. This Farmer's Almanac link will give you your first and last frost date by zip code. Where we live, I can generally expect our last frost date to be around May 15 and the first frost often comes by October 15. This gives me around 150 frost free days in an ideal world. To play it safe I round down and look for varieties that will mature under 120 days.
Ok, got it. So how to plant for continuous harvest?
Start seeds 4-8 weeks ahead of each season. With a little forthought you can have your seedlings ready to go in the ground when old crops come out.
**Dec-Feb: Winter- Start spring transplants in late winter indoors. Includes cabbage, lettuce, greens, broccoli, cilantro, dill. Gardeners in southern latitudes (or very ambitious gardeners elsewhere!) will even start their tomatoes, peppers and eggplants during this timeframe for transplant in March-April depending on last frost dates.
**Mar-May: Spring- Transplant starts from above. Start new rounds of greens. Direct sow root crops like carrots/beets. Start warm season crops peppers, tomatoes and eggplants 6-8 weeks before last frost. Start cucurbit (melons, cucumbers, squash) crops only 2-4 weeks before last frost or even better, direct sow.
**June-August: Summer- Transplant any summer crops you started early and direct sow other summer crops such as corn and squash. Start fall crops in mid to late summer. If temps are very hot start these in the shade and raise them under shade cloth. Direct sow under row cover laid straight on the ground for carrots and beets.
**Sept-Nov: Fall- Transplant fall crops and direct sow fall/winter crops. For a successful fall/winter garden it is crucial that crops are planted early enough to produce. If you wait until November then growth is small and stunted and you won't be eating until the spring when those same crops are likely to bolt to seed.
More tips for a continuous harvest
1. Plant different varieties of same veggie with earlier and/or later maturity dates to extend your harvest window. Pay attention to the 'days to maturity' information on seed packets and online. Usually for crops most often transplanted, like tomatoes, this is from the date of transplant. Most others are for direct sowing. For example, be sure to plant some ultra early tomatoes that mature in 60-70 days along with your main season large fruits to extend your tomato eating.
2. Plant crops in succession. Good candidates for this include carrots, beets, turnips, lettuce, beans, cucumbers, basil, squash and corn. Every 2-3 weeks plant a new round of these veggies. This way your harvest will not all come in at once but instead be spread throughout the harvest season. When plant production begins to taper you can pull them out to make room for transplants you may have waiting in the wings.