Techniques in the propagation business have advanced in recent years to suit different production methods and market timing. Nowhere is this more evident than in strawberries. 

While Carther Plants started in 2000 with vegetable plugs, it’s been strawberry plugs that have boosted their business in the last five years. As strawberry growers experimented with high tunnels, their needs were for plug transplants rather than bare root plants for a faster start. An initial order for custom propagation to Carther Plants, Thamesville, Ontario has grown into a much larger business. Plants are now shipped to growers as far afield as British Columbia, Prince Edward Island and California.       

“We have more biosecurity at all stages,” explains Sandra Carther, Thamesville, Ontario.  The 35,000-square foot greenhouse operation uses screens to ward off insect invaders and houses all stages of the nursery crop from start to finish within the greenhouse. Just as important, the original plantlets come from the Ontario Plant Propagation Program in New Liskeard which tests all germplasm for viruses. When they arrive at Carther Plants in the spring, the strawberries are grown in a soilless medium to prevent soil-borne nematodes and anthracnose.

Ontario berry growers start planting bare root strawberries in April and May, then typically plant plugs late August and into September. Summer-planted plugs enable picking to start earlier the following spring and help to take out the peaks and valleys of the production season. With the greenhouse-grown nursery stock, growers can also increase the flexibility in planting dates by using chilled plugs, which are held in cold storage and can be planted at almost any time of the year.

One customer, Bruce Parks, who operates Parks Blueberries near Bothwell, Ontario, has taken advantage of this. He has seen good results in the first year along with the added benefits of clean planting stock. “We planted chilled plugs this past spring and didn’t spray them once for insects or disease all season,” he says.   

It’s been a learning process for the Carthers propagating different strawberry varieties. Day-neutral varieties such as Albion and San Andreas react differently to temperature, day-lengths, and even fertilizer levels than June-bearing varieties. 

“There’s a lot of interest in day-neutrals,” says Carther. “Growers are looking for season-long productivity.”

A few farmers are investigating how to grow strawberries hydroponically to conserve water resources. The varieties they choose will depend on the production system, lighting levels and market timing. Strawberry plugs are needed for a hydroponic system. 

Carther Plants gained organic certification in 2013 for part of the greenhouse. In 2016, they will be offering eight June-bearing strawberry varieties and two day-neutral varieties.

PHOTO CUTLINE A: Sandra Carther demonstrates strawberry plugs at the 2015 Ontario Fruit and Vegetable Convention.

PHOTO CUTLINE B: Custom rooting provides a healthy plant free from soil-borne diseases such as anthracnose. Photos by Denis Cahill.