How to Start Your Fall Garden - When and What to Plant for Late-Season Harvests

When the middle of summer rolls around you’re sure to be in garden heaven. The picking of zucchini, cucumbers, tomatoes, peppers, beans, basil and more is non-stop and maybe even a little overwhelming. For the next six to eight weeks you won’t be going hungry and your tastebuds will be loving it. But the bounty of summer precedes the inevitable in Canada, most of the U.S., and much of the temperate growing zones in the northern hemisphere - fall is coming. And that’s not going to work for your summer-loving veggies. But here is some good news: just because cooler weather is closer than you think doesn’t mean the bounty has to stop. In fact, it’s the perfect time to start thinking about what you can grow in your fall garden. By planting the right cold-hardy crops in late summer, you’ll be enjoying backyard produce right until the first snowfall. 

While the colder temperatures and shorter days of fall makes growing trickier, there are many veggies that will thrive. To get going, follow these tips: 

1. Start Early 

If you’re wondering when to start fall seedlings or sow fall seeds, the answer is sooner rather than later. Don’t wait for a sign of the seasons changing, or it will be too late. The key to a great fall garden is to give plants a summer head-start. The sun and heat of August and September will give seeds and seedlings time to establish and size up before the first frost. This is especially important for longer-growing fall crops like brassicas (cabbage, broccoli, brussel sprouts etc.) and carrots. Quicker growing crops like spinach, lettuce and leafy greens can be planted later, or even twice, in the fall season. Be aware of the “days to maturity” for what you’re planting – which is found on the seed package or plant tag.  

2. Make Room

One of the hardest things for any gardener to do is pull out plants. It’s hard enough when things have died and you realize the end has come. But even more difficult is making the decision to remove plants that may still be growing. Don’t be fooled. A summer-veggie plant still alive is not the same as a thriving one. Keeping them in the garden to grow in less than ideal conditions, without enough time for fruits to form again, is a waste of space. Clear out anything that is past its prime or has slowed down its output and make way for fall crops that will be far more productive. 

3. Extend The Season

Your fall garden lifespan can be extended even longer with poly tunnels, floating row covers and cold frames. These structures topped with clear plastic, old windows etc. aren’t meant to keep plants growing like a heated greenhouse would – there’s not enough sun energy at the time of year for that – but rather just to protect them from harsh conditions enough to keep full-grown plants alive so you can harvest as you need. The 5 to 10 degrees of insulation these provide can be the difference between chilled and killed plants. This turns your garden into a giant refrigerator that helps crops hold their quality longer while you enjoy them. With the right care, and a little luck, you can be eating from your yard late into the year. 

BONUS: Another way to extend the fall garden season without any covers is to grow in raised beds. Even slightly elevating your garden keeps soil warmer and plants protected from ground frost that would kill in-ground gardens. If you’re thinking about converting your garden or adding raised beds to your yard you can shop standard raised bed sizes or reach out for more information on a custom installation.

Now that you know the basics and are ready to go, it’s time to pick the right crops and get them started. Here are some of my favourites and the latest that I will be starting and transplanting them in my Greater Toronto Area garden (6a growing zone).

Fall Planting Guide

Kale: Start transplants from seed in early to mid August and plant out in the garden by early September for harvesting through November. Protect with row cover to prevent cabbage moth caterpillar damage until October. 

Lettuce/spinach: Sow directly from seed or start final transplants in late August and plant out in the garden by mid September to be ready in October

Radish: Seed directly in early September for an October harvest. 

Beets: Sow seeds in mid-August to reach maturity by mid-October.

Carrots: Sow seeds in early-August as these need approximately 80 days to mature. They can be left in the ground before the first frost and picked as needed if the tops are covered with leaves, mulch or a protective cover. 

Green Onions: Sow seeds or transplant in early-August. Green tops can be harvested at any time, or bulbs can be pulled all autumn long. Any onions left in the soil will die back and return in spring.

Broccoli: A longer growing fall crop, plan a 90-100 days growing season before the first frost. Seeds should be started in mid-to-late July and transplanted in the garden by early August. 

Brussel sprouts: Start from seed or transplant in early August to ensure stalks and sprouts have enough warm weather to grow ahead of an early-to-mid October harvest.

Rapini: Sow directly from seed in early August for harvest in early October.

I want to know what you’re planting in your fall garden. Leave a comment below or share on instagram and tag @theyoungnonno.

Buon giardinaggio!