So, you have an idea of which vegetables you want to plant. But when should each vegetable be planted? How early can you plant tomatoes? How late can you plant pumpkins? Do you really plant potatoes on St. Patrick’s Day? This will help you determine when to plant your vegetables in the garden.
There are a few factors which will help us figure out when to plant which vegetables in the garden:
- Your Local Frost Dates: Frost date is the average date of the first or last light freeze that occurs in spring or fall.
- For each vegetable, we plant a certain number of weeks before or after the frost dates, depending on how frost-tolerant that vegetable is. Many plants will suffer or even die if hit by a frost (though not all!).
- Frost also gives us a sense of the soil temperature, which is another factor that affects planting.
Of course, we need to remember that nature is unpredictable. There’s always a chance that a sudden frost can hit our garden at an inopportune time. However, we can also protect our garden from frost.
Spring Planting Considerations
In the early spring, we plant cool-season vegetables. The biggest issue in spring is the soil temperature since we’re directly following winter, when the ground may have been frozen. As most regions experience some sort of frost, the soil needs to warm enough for seeds to germinate. And it can’t be too wet, either, or the seeds will rot.
While frost dates are a general guideline and fine for beginners, knowing your soil temperature is an even more accurate factor to rely on. Frost dates are based on historical averages and predictions, so they can vary quite a bit from year to year. Soil temperature readings, on the other hand, are cold, hard numbers!
However, to determine the soil temperature in your garden, you need to buy a soil thermometer. They are not expensive. You simply insert the thermometer a couple of inches in your soil for a few days in a row to get a reading. Go slightly deeper if you are planting transplants instead of seeds.
Some spring-planted crops mature quite quickly and others more slowly, so it’s important to know the maturity dates from your seed packet to understand how to schedule your plantings.
- Plant cool-season veggies that mature quickly (lettuce, spinach, leafy greens) and are also harvested in spring.
- Plant cool-season crops that mature in early summer (peas, broccoli, cabbage, and others)
- Stagger any crops that have a very short harvest period (peas, radishes, turnips). For example, many radishes mature in 21 days or so, and you want to harvest them when they’re mature or their taste becomes woody. So, instead of planting all your radish seeds at once and being forced to harvest them all at once, stagger plantings 7 to 14 days apart.
Of course, you can start seeds indoors in late winter to get a head start on spring. This is helpful for people who live in the far north and have a short growing season.
Summer Planting Considerations
The “warm-season” crops cannot be planted until the soil has warmed up enough, which generally doesn’t happen until late spring or early summer, depending on your climate. Crops such as peppers, melons, and tomatoes need a higher soil temperature and are very susceptible to frost. If you plant too early in cold spring soil, the seeds will not germinate or be of poor quality. Transplants will also grow very slowly.
Here at the Almanac, there’s a piece of folk wisdom that says that all plants in summer—no matter when they were set in the ground—will catch up by the end of July. In other words, faster growth during warm weather will even allow late plantings to catch up with early plantings made before the soil is warm enough.
Again, note the maturity dates listed on the seed packets as you plan your planting schedule.
- Some warm-season crops have short harvest periods, such as bush beans and sweet corn. Many warm-season crops with short harvest periods can be planted successively throughout the early summer season, which will extend the harvesting period.
- Other warm-weather veggies such as squash, tomatoes, and pole beans will be produced for a longer period, so you typically only need one planting.
Fall Planting Considerations
We call this “fall planting” because the crops mature in the fall, but they get planted in mid-to-late summer. Not all beginners will do fall planting, but there are indeed some big advantages for some gardeners to extend the season. First, the ground is already warm! It’s much easier to start plants. Second, there are fewer bugs and pests. Try to extend your season for maximum harvest!
- Mid-summer is a good time to plant warm-season crops with a short harvest period (bush beans, corn).
- Also in mid-summer, you can plant autumn veggies that mature slowly (parsnips, rutabagas, brussels sprouts, and others)
- In late summer, as the weather cools a little, plant vegetables that mature quickly (lettuce, radish, others).
How to Calculate Your Last Planting Date
- First, determine the average date of your first fall frost.
- Then, look at your seed packets, which should tell you how long each plant will take to mature, and back out those days from the fall frost date.
- Then, back out another 10 to 14 days to allow for harvesting.
- Finally, because fall days are cooler and shorter with less direct sunlight, we need to add a “fall factor” and back out an extra 7 to 10 days.
For example, the days to maturity for Black Seeded Simpson lettuce is 45 days. Add 14 more days for harvesting, and then add 7 more days for a ″fall factor.” This means a total of 66 days. If your fall frost is around November 1, you’d need to back this out by 66 days and plant your seeds by August 26. If you plan to offer your plants protection, you can plant 2 to 3 weeks later and still expect to get a good harvest.
Also, here is some advice on which vegetables to plant in the fall.
- Before the first fall frost, you’ll need to harvest those warm-season vegetables: pumpkins, winter squash, tomatoes, melons, peppers, and beans.
- However, there are cool-season vegetables that can stay in the ground after frost but before the ground freezes as long as you much the ground: turnips, rutabagas, and winter radishes.
- Also, some veggies can stay in the ground until the temperature dips below freezing: cabbage, Brussels sprouts, collard and kale, kohlrabi, chard, and spinach.
- Garlic is also planted in the fall, for harvesting next summer!