Skip to content

Start these 15 Seeds in August for a Bountiful Fall Harvest

August is one of the busiest months for gardeners everywhere, and after a full day of weeding, watering, and harvesting, starting another round of seeds is probably the last thing on your mind.

Keep reading and let us convince you why sowing fall seeds should be on your August to-do list. Not to pile on the work, but planting seeds for a fall harvest is the best way to get the most out of your garden. Nearly everything you started back in early spring will thrive in autumn, too—and you can enjoy twin harvests of your favorite veggies.

Fall gardening is just as enjoyable as summer gardening, if not more so, since the weather is significantly more bearable. The days are cooler and it rains more frequently—meaning that you have to water less. Pest pressure is also typically less intense than in midsummer, and some of the best-tasting, most nutritious vegetables thrive in the cooler months.

Keep reading for 15 easy-to-grow vegetables that you can start from seed this month for an abundant autumn harvest.

15 seeds to start in August

Depending on where you live, you might be able to get away with more varieties than these—but growers in most hardiness zones can successfully start any of these 15 seeds in late summer.

Salad greens

Leafy green vegetables tend to die back during the dry midsummer heat but these same plants thrive in the cooler temperatures that autumn brings. If outdoor temperatures are too hot for your seeds to germinate, try putting the seed trays in a walk-in cooler or a root cellar where temperatures are much cooler.

  1. Lettuce

  2. Spinach

  3. Mustard

Brassicas

Cole crops prefer cold weather, so they’re ideal for fall. Many brassicas are hardy enough to overwinter in milder climates, so you can really get two harvests out of one planting! 

  1. Kale

  2. Kohlrabi

  3. Collards

  4. Cabbage

  5. Broccoli

  6. Cauliflower

  7. Brussels sprouts

Root Crops

Many root crops (especially carrots and parsnips) get sweeter after a frost, so don’t hesitate to seed another row of these cool-weather crops in late summer. Leave the roots in the ground until you’re ready to use them—the best place to store root crops is actually in the ground!

  1. Radishes

  2. Turnips

  3. Parsnips

  4. Beets

  5. Carrots

5 good reasons to start seeds in August

Summer seed sowing can be a lot of fun—and more comfortable, too—since you can easily do this work from the air-conditioned comfort of your own home. Need we say more?

1. Access to in-season vegetables

Our bodies are naturally drawn to different vegetables at different times of the year. We just can’t get enough juicy tomatoes and watermelons in the peak of summer, but in autumn we crave calorie-dense foods like beets and kale.

Since these vegetables may not always be available at local grocery stores, the best way to secure access to these foods is by growing them in your own garden.

2. Twin harvests

In areas that get four distinct seasons, cold-season crops thrive in both spring and fall, which have similar growing conditions. With proper planning, you can easily get a second harvest of the same vegetables that you started in spring—and in our opinion, they taste even better the second time around. 

3. Fewer pest problems

If you’ve spent any time gardening, you know that midsummer is the peak season for pests. Fortunately, as the days get colder and the nights longer, many insects complete their life cycles and insect damage becomes less of an issue.

This doesn’t mean that you can let down your guard completely—cabbageworm and corn earworm in particular may still be an issue in the fall garden. However, pest pressure in September is significantly less than pest pressure in July.

Use the all-natural pest control methods here to keep pests from overrunning your fall garden.

4. Less need for irrigation

In most regions of the world, autumn brings more precipitation than summer. While this doesn’t mean that you can pull up your irrigation systems just yet, it does imply that you will have to water less as it begins to rain more.

5. Cooler weather to work in

As nice as warmer weather is at the beginning of summer, working in the heat of the day gets old fast—and in the South, it can be downright dangerous. Working in the garden in fall temperatures can be much more pleasant than in the summer, and you might even be motivated to get more done!

Tips for starting fall seeds

Starting fall seeds is very similar to spring seed starting, with a few minor differences:

Choose hardy plants

Most cool-season crops are frost tolerant, but make sure as you’re shopping that you’re choosing semi-hardy or hardy varieties that can survive at least a light freeze, in case your first frost comes earlier than expected.

Opt for fast-maturing varieties

Spring and fall are often shorter growing seasons, as the world is transitioning from winter to summer. For this reason, it’s imperative to choose quick-maturing varieties and start seeds at the right time. Most hardiness zones in the US experience their first frost in late September or October. Counting back to August, that leaves about six to twelve weeks before the first killing frost of the season. Opt for varieties that mature in 60 days or less to get the most out of the garden before the onset of winter.

Prepare the soil

Many of our favorite summer crops are heavy feeders, so you’ll need to amend the soil before planting or seeding any fall crops. It doesn’t hurt to do a soil test to see exactly what your soil needs, but if you’re pressed for time, an application of an all-purpose balanced fertilizer and a layer of compost will often do the trick.

Direct sow

Seeds need moisture to germinate, so look at the forecast and plan to direct seed fall seeds immediately after or before rain, then keep the soil wet until seedlings germinate.

Plant fall seeds just a little bit deeper than spring seeds, to encourage the seedlings to develop strong root systems that will prepare the plants to survive cooler weather.

Starting seeds in trays

Many fall seeds can be direct-seeded in the garden without issue, but you can start seeds in trays for more control. Unlike spring seeds, you don’t have to start fall seeds in a greenhouse or cold frame (and it’s often better if you don’t, since the greenhouse may be too hot for many plants that prefer cool temperatures).

Especially heat-sensitive plants like lettuce and spinach actually prefer to be started in a cool area, like a cellar or even a walk-in cooler. You can also start these seeds on a table in a shady area of your yard. Just make sure that when the seedlings do sprout you move them to an area that receives direct sunlight, to prevent the seedlings from becoming too leggy.

Provide continuous moisture

Give fall crops at least an inch of water a week for the healthiest plants. Drip irrigation is the best watering method since it conserves water by applying it directly at the base of the plants. Mulch mature seedlings to conserve even more moisture in late summer’s heat (plus the mulch will keep plants warmer when the weather turns colder).

If you start seeds in trays, use a humidity dome to keep the soil moist (but don’t forget to vent the seed trays around midday, as the temperature could get too hot underneath the dome).

Protect fall crops with frost cloth

Even though fall crops are better equipped to handle colder weather, severe dips in temperature can still cause damage. Cover your rows with frost cloth during the coldest winter nights for a little extra protection from deep freezes. Frost cloth can raise the air temperature underneath between five and ten degrees Fahrenheit, depending on the weight of the fabric.  

August is a great time to start fall seeds for a second harvest of cool-season crops. The fall seeds in our collection include leafy greens, brassicas, and root crops, as well as herbs.

Even though it adds work to your August to-do list, there are more than a few advantages of starting seeds in late summer, so don’t delay in putting that seed order in! Shop our full collection of fall seeds today to find the perfect cool weather and increased moisture seeds for your garden and your family to enjoy this autumn. 

Previous article 7 of the Best Mulches for Vegetable Gardens (Why Mulching is Essential)
Next article The Complete Guide to Canning (Plus 4 Other Ways to Preserve Your Garden Harvest)