Summer Squash – A versatile, easy-to-grow crop for containers

by Steven Biggs, writer and garden blogger

The meals on the cross-country Via Rail train featured plates inspired by well-known Canadian ingredients such as bison, salmon, and maple syrup. So I was a bit surprised when I saw a cluster of top-like vegetable on my plate, some bright yellow, some forest green, and some a translucent white. I didn’t realize that, despite the exotic appearance, I was staring at cousins of the common zucchini, fellow summer squashes.

SteveSquash-flowerWhile we harvest winter squash, such as the well-know butternut squash, when the skin is hardened and the seeds mature, we harvest summer squash while the skin and seeds are immature, soft and edible.

A perfect candidate for container gardening

Some summer squash varieties have a vining habit, while some have a bush habit. Both are suitable for growing in containers. Train vining varieties along railings or trellises, and use bush types when you want the plant to stay in its designated place.

Choose from a wide variety of types: Crookneck varieties owe their name to a club-shaped fruit sporting a bend in the neck. Straightneck varieties are...self explanatory. Some are scallop shaped, with the round, flattish fruits having scalloped edges. Then there is the cousa, a light-green, club-shaped variety from the Middle East, where it’s hollowed out and stuffed with meat and rice. Look for other interesting varieties shaped like papayas and stars. The well-known zucchini is long and slender, most commonly with a speckled green skin.

Growing summer squash

Not only are they easy to grow, they are prolific producers. Be careful not to plant too many or you might find yourself giving away more than you eat.

  • Plant seeds directly in the container, about 1 inch deep in groupings of 2 or 3, once the danger of frost is over. Thin to a single plant once seeds have germinated. 
  • Or start early by sowing seeds indoors about 3 weeks ahead of last frost. Use peat pots, which minimize the shock from transplanting.
  • Transplant outdoors after the last frost, leaving approximately 2 feet between bush-type varieties, or 1 foot between vining varieties being grown up a trellis or along a railing. 
  • The site should be sunny and warm. This is why containers are perfect for growing summer squash. The soil in the containers heats up faster than the soil in the ground does. 
  • Soil and nutrition are important. Amend the soil with lots of organic matter. Unlike their garden brethren, plants grown in containers have their roots restricted to a small area, so ensuring sufficient food is important. So don’t forget to fertilize, as the plants can quickly exhaust soil nutrients in containers.Maintenance is simple: don’t allow the soil to dry out. Summer squash guzzle a fair bit of water, so keep plants evenly watered—meaning don’t let them go from alternately bone dry to sopping wet. Extremes like this can cause abortion of young fruit and poor growth. 
  • Pick summer squash when they are young and tender. They are better for eating when young, and constant picking stimulates the plants to produce more fruit. Pick straight-type fruits when they are less than 6 inches in length; and pick scallop-shaped fruit when they are less than 3 inches across. 
  • Pests include striped or spotted cucumber beetles, which munch on the leaves. They make their appearance in my summer squash plants every year, although they have never caused sufficient damage to warrant treatment.
  • If you like to save your own seeds, towards the end of the season allow one fruit to ripen fully, then harvest seeds for next year.

Get Cooking

If you have more summer squash than you can eat, try some of the blossoms too. Sauté them in butter, or dip them in batter and deep-fry them.

  • Here are some ideas for using summer squash:
  • Pan-fry them in butter.
  • Stuff and bake them, like the Lebanese-style cousa. 
  • Barbecue them whole or sliced, with or without marinade. 
  • Make a minestrone-style soup, adding both fruit and flowers. 
  • Stew with tomatoes and onions to make a delicious side dish, topped with parmesan cheese.

Steven Biggs is a freelance writer, horticulturist, and food lover. Next to gardening, one of his favourite pastimes is cooking and preserving food he has grown or sourced locally. His work in horticulture and agriculture spans western Canada, Ontario, Quebec, and England. Learn more about his gardening ideas at his edible gardening website,