Spring is prime time for cool season salad greens like lettuce and spinach but these are also great crops to plant in late summer for fall harvesting. Most salad greens thrive in the cooler temperatures and increased moisture of autumn. If planted in a cold frame or greenhouse, certain greens are even cold tolerant and can be enjoyed all winter long in many parts of Canada.
There are two ways to plant salad greens for fall harvesting: 1) Direct sow seeds in garden beds. 2) Start seeds indoors and then transplant the seedlings to the garden. I base my seeding method on the actual type of green. Some grow best when direct seeded while others appreciate the indoor head-start. See the below list of greens for specific advice on how to start each type.
The biggest challenge in summer is establishing salad crops when the weather is hot and the soil is dry. To overcome these issues, I water new seed beds or transplanted crops often to keep the soil consistently moist. I also erect a mini hoop tunnel made with wire hoops over the bed. This simple structure is then covered with a piece of shade cloth or row cover to provide shading and reduce water evaporation. I leave it in place for about a week to reduce stress on the young plants.
Also don’t forget to sow seeds for salad ingredient veggies like salad turnips and radishes. These are super quick to grow and also love the autumn weather. They can be sliced thinly to add crunch to salads.
Here are five of my favourite salad greens for autumn:
There are many wonderful types of lettuce to grow in the fall. I love planting looseleaf, Oakleaf, romaine and butterhead varieties. Because lettuce seed doesn’t germinate when the soil temperature is above 27 C, I give my lettuce a head start indoors under grow lights. I sow several crops for fall and winter harvesting beginning in mid-August and into late-September. Once the seedlings are about three weeks old, they’re hardened off and moved to my garden beds, cold frames, and polytunnel. If you wish to harvest into winter (beneath a garden cover), choose cold hardy varieties like North Pole, Winter Density, and Red Salad Bowl.
Spring-grown spinach is a delicious but short-lived salad green as the plants bolt quickly once the weather heats up in late spring. Therefore the best time to grow spinach is in fall when the shrinking days and cool temperatures provide perfect conditions for top quality spinach. Direct seed spinach from late August through late September for months of nutritious greens. For baby spinach, I grow a smooth leaf type like Covair or Seaside. I also love the large, crinkly leaves of the classic spinach variety, Bloomsdale which is hardy enough to stand all winter long in cold frames and greenhouses.
I’m a big fan of the peppery flavour of arugula and this gourmet green is very easy to grow in garden beds and containers. Like spinach, it’s cold tolerant and can be harvested from early autumn though mid-winter when protected. Standard arugula yields deep green, lobe-shaped leaves that are harvested as a baby crop or when mature. This is a quick-growing salad plant and goes from seed to harvest in about four to five weeks. It’s therefore important to make several plantings. I direct sow arugula seeds every two weeks from late August through early October for months of salads.
Love it or loathe it, kale is a salad green that offers a lot of healthful benefits. I prefer kale as a baby green and therefore direct sow seeds for varieties like Lacinato or Red Russian densely in late summer for a bumper crop of baby kale. For this type of planting, try to space the seeds one to two inches apart. For large plants, I start the seeds indoors in mid to late summer in three inch pots under grow lights. Once the seedlings are two to three inches tall, they’re hardened off and transplanted in the garden. Space kale plants twelve to eighteen inches apart. To enjoy into winter, cover plants with a mini hoop tunnel in late autumn.
Mizuna is a type of mustard green with green, purplish-green, or deep purple leaves, depending on the variety. The leaves are often toothed or finely divided and this is a green that adds both beauty and a mild spiciness to salads. Direct sow mizuna seed beginning in late August through early October. Outstanding varieties include Miz America, Purple and the standard green.