Dear Helen: I’m house-sitting briefly on Saltspring Island, before returning to my Ontario home. I read in one of your columns about growing sweet potatoes. How is this done, and is there a source for planting stock in the Victoria area? In my Ontario garden we are frost free from June 1 to the end of September. Would that work?
J.C.
It probably would. We have a longer growing season here, but a cooler one. In Ontario you have the heat units the plants need.
Sweet potatoes are grown from rooted cuttings, which are available at Bella’s Berries and Farm Fresh Produce in Brentwood Bay (250-652-3082).
Sweet potatoes need warmth, full sun and a soil not overloaded with organic matter. A sandy loam is best, and it does not need to be very fertile. A raised bed is ideal. To pre-warm a prepared site, place a sheet of plastic over it. Clear plastic warms the soil at deeper levels; black plastic stops weed growth. Take your pick.
In late spring, when air temperatures have lost their spring chill and the soil is thoroughly warm, cut circles 23 cm (nine inches) in diameter and 45 cm (18 inches) apart in the plastic to receive the cuttings. An initial covering with a floating row cover or clear plastic tunneling helps to give the plants a good start.
With summer’s warmth the vines start running vigorously and producing morning glory type flowers. Tuber development usually takes place between mid-August and mid-September.
Once soil temperatures drop below 15 C., the tubers stop growing and should be dug up. They must never be allowed to cool below 10 C, either in the ground or in storage.
Dear Helen: What are the little pink lilies that I see blooming in the Cowichan area in April?
B.A.
They are most likely Erythronium smithii, commonly called Pink Easter Lily. They are found mainly in Sooke and Lake Cowichan northward.
A gardener in Sooke wrote recently to describe woodland areas on her property where they grow. She gathers and spreads seeds every year to create more plantings on the property.
Dear Helen: Is it all right to add raked-up lawn thatch to the compost? In the shaded parts of my lawn I rake up moss along with the thatch.
L.A.
Moss in moderation is probably all right in a compost. Add it in shallow layers or, ideally, at the bottom of an emptied heap about to be re-built with garden trimmings. This latter option would help to ensure complete breakdown of the moss.
Though adding moss to compost does pose the risk of spreading moss in the garden, moss will not take hold where soil and site conditions do not favour it. I’ve placed small amounts on compost heaps and never observed a problem in the vegetable plots where I use almost all the compost.
Except where potatoes will be planted, I habitually lime vegetable plots ahead of adding compost and planting. Liming helps to inhibit moss growth. Moss thrives best in shaded areas with wet, compacted, acidic soils.
GARDEN EVENTS
Dahlia meeting. The Victoria Dahlia Society meets Thursday, 7:30 p.m., in the Wellesley retirement home, 2800 Blanshard St. (entrance on Market Street). Topic for the evening will be dahlia flower types, sizes and forms.
Hospice tour. Victoria Hospice is hosting its ninth annual Teeny Tiny Garden Tour on Sunday, 9:30 a.m. to 5 p.m. The tour offers a glimpse into a dozen of Victoria’s smallest backyard gems. Also included will be Abkhazi Garden, a one-acre community treasure. Tickets at $25 are available at Thrifty Foods, Dig This, Capital Iron downtown, Mayfair Shopping Centre concierge desk, Victoria Hospice Thrift Boutique and Victoria Hospice.
Cowichan Valley tour. Cowichan Family Life, a Duncan-based agency that provides counselling and other support services to families and individuals, will present its 20th Annual Cowichan Valley Garden Tour Sunday, 10 a.m.-5 p.m. The self-guided tour of six beautiful gardens includes an eight-acre lakeside property, another with drought resistant plants in gravel, and the large rock outcroppings and hillsides of Misty View Farm, where tea will be served and I’ll be chatting with visitors from noon to 3 p.m. Tickets at $20 are available at the CFL Thrift Store, 531 Canada Ave. in Duncan and at garden businesses in Victoria, Duncan, Nanaimo, Chemainus and Mill Bay. For a source close to you call 250-748-8281.