The Right Time to Plant in Ontario

If there's one question we get more than any other, it's this: when should I plant?

The honest answer is that timing matters more than most people think, and getting it right can be the difference between a plant that thrives and one that just survives its first year.

There's also the matter of dormancy. In spring before leaf-out, and in fall after the growing season winds down, most woody plants and perennials are either entering or coming out of their resting state. Transplanting during this window means you're moving a plant that isn't in full resource-demand mode — it's not mid-flower, mid-flush, or pushing new growth. That makes establishment significantly less traumatic for the plant.

This doesn't mean summer planting is impossible. It just means you'll be working harder, watching soil moisture closely and watering more frequently during the warmest weeks.

Watch Out for Wildlife

If you're in an area where rabbits, deer, or moles are common, be aware that freshly planted stock can attract them. Many animals can detect disturbed soil, and a newly planted bed can read as an open invitation. Planting in spring or fall doesn't eliminate that risk, so if wildlife pressure is a concern in your garden, plan to protect new plantings accordingly with fencing or repellent.

The Exception: Annuals

Annuals are a different story. Because they complete their full life cycle in a single season, they're not going through the same kind of transplant stress as a perennial or shrub. But they are frost-sensitive, which means planting too early will set them back or kill them outright.

In most of southern Ontario, the last frost date is typically around the beginning of May, though this varies by region (Muskoka and northern areas run later). We recommend waiting until after your local last frost date before putting annuals in the ground or moving tender plants outside.

A Practical Rule of Thumb

• Perennials, trees, and shrubs: plant in spring (as soon as the ground is workable) or fall, at least four to six weeks before freeze-up
• Annuals and tender plants: wait until after the last frost, and to be safe, until end of May in most of Ontario

Plant at the right time, give the roots a chance to find their footing, and you'll spend a lot less time worrying — and a lot more time enjoying the garden.