When to plant Peony and remove winter covers

(Question)

Hi There!

I’m looking for some advice on opening up my garden for spring. Many of the bulbs available at garden centers (e.g. Peony Bulbs) as well as several guides for opening up suggest waiting until the last spring frost to plant them or take action. The last frost in Toronto (apparently) is in Mid May, is that accurate?

I would like to know:
1) When should I plant bulbs that say to wait until after “the last spring frost”
2) When should I remove burlap / winter coverings from my least hardy plants (e.g. hydrangeas)?

I’m sorry if these answers are on the website – I wasn’t able to find it specifically! Thank you in Advance, Dan

(Answer)

Hi,

Thank you for your question to Toronto Master Gardeners. You are correct about the average last frost date being mid May in Toronto. It is advisable to wait until the ground is not frozen for planting peony roots so that they will have a chance to expand and settle in before the heat of summer. Peonies dislike being moved once established, so be sure to find the right location with enough sun.

Go ahead now and uncover your Hydrangea and other perennials . I don’t cover mine because the flower heads give winter interest to the garden.  For advice on when to prune Hydrangea and other shrubs and trees, refer to The Pruner’s Bible by Steve Bradley (Rodale, 2005).

A good all round book on gardening in Ontario may be of interest to you.  Some of these include Gardening Month by Month in Ontario by Alison Beck (Lone Pine Publishing, 2003) and Mark Cullen’s Ontario Gardening (Penguin Canada, 2002).

Tip: The advice on most labels is accurate because of intense plant trials and nursery experience. I save mine on shower rings and hang them up so I can refer to them for pruning and other requirements.

Happy Gardening!

5 Apr 2021