Dear Helen: My lettuces dried up in the heat and dry conditions of June. Can lettuce not be grown successfully in hot weather?
Fine lettuces can be grown through the summer, given certain parameters. First, consider your variety selection. Most lettuces grow best in cool spring and fall weather, but some have enough heat tolerance to produce well through the summer. Catalogue listings and seed packets indicate suitable varieties.
The Johnny’s Selected Seeds catalogue begins its vast lettuce listings with a charted guide to preferred varieties for early, mid, and late season harvesting. The mid season varieties are planted in late spring and early summer for hot weather (mid and late summer) harvesting. Among them are Skyphos and Red Cross (red butterheads), Coastal Star (romaine) and New Red Fire (red leaf lettuce).
Johnny’s beautiful, tasty Salanova lettuce blends “hold their flavour without growing bitter.” I’ve found the Salanova Home Garden Mix to be very reliable for growing spring through early autumn.
Among its butterhead lettuces, West Coast Seeds notes that Buttercrunch “doesn’t become bitter in hot weather” and Alkindus is “very slow to bolt (to seed). Ours stood in the field trials into mid-August.”
It’s worthwhile trying a few new varieties each year, to determine the most reliable in your conditions for summer growing.
For the easiest possible summer lettuce production, find or create planting sites that provide shelter from the hot afternoon summer sun. Move seedings and transplants to lightly shaded areas as the weather begins warming in spring. In fully open, unshaded gardens, transplant lettuces on the north (shaded) side and right at the bases of tall plantings like staked tomatoes and trellised pea vines.
If no natural prospects for shade exist, suspend some sort of lightweight material over the transplants. That could be old window screening or lacy curtaining. Commercial shade cloth is available. If you can’t find it locally, it is listed in the Lee Valley Tools catalogue.
Another key element in successful lettuce growing is the soil. A fertile, humus-rich, moisture retentive soil gives the plants the best possible support for good growth. A plump soil produces plump lettuces.
Lettuce needs water. Don’t let the soil dry out. As temperatures rise, arrange a heat-reflecting, soil-shading, moisture retaining mulch around the plants. Chopped straw and dried grass clippings are examples of materials useful for this purpose. They can be helpful also around many other vegetable plantings, such as pumpkins and squashes, in the summer.
Picnic in the gardens. Horticulture Centre of the Pacific, 505 Quayle Rd. in Saanich, invites the public to bring their own food for a picnic with live music in the gardens this evening. Browse through the works of local arts vendors, visit a Master Gardener booth, and check out the plant sale. Admission is by donation between 5 and 8 p.m. hcp.ca.
Dahlia meeting. The Victoria Dahlia Society meets Thursday, 7:30 p.m., in The Victorian at MacKenzie, 4000 Douglas St. The program will be on Growing Dahlias for Cut Flowers: Making bouquets for pleasure and profit. All visitors are welcome.
Flower show. The Victoria Lily Society is hosting its Summer Scentsations Flower Show, Plant Sale and Tea on Saturday, 10 a.m. to 4 p.m. at Cadboro Bay United Church, 2625 Arbutus Rd. in Saanich. View judged exhibits of lilies and roses, ferns, cut flowers, herbs, fruits and vegetables. The plant sale will have potted lilies, woodland plants, peonies and more. English-style tea or coffee with treats will be available for $5. Admission is by donation. Free parking. This is a wheelchair accessible event.
West Shore tour. Soroptimist International of Victoria Westshore is hosting its first Westshore Garden Tour of six beautiful View Royal, Colwood, Langford and Mechosin gardens on Saturday, 10 a.m. to 3 p.m., followed by a Garden Gathering at Down to Earth Gardens and Nursery, 1096 Derrien Place in Metchosin. This fundraiser will enable the club to help women and girls reach their potential, support their families, and give back to the community. Tickets, $25, at SIVW.ca/WGT and at Down to Earth.