Best Lilacs for Northwest Territories

A lilac in full bloom in June, with the scent drifting across the yard, is a sight the Northwest Territories can deliver when the right shrub goes in. Hardy common lilacs, a late bloomer and a compact Korean type all earn a place in a territory with a very cold winter and a short season.

Best Lilacs to Grow in Northwest Territories

The lilacs that hold here are hardy common lilacs, a late-blooming hardy type and the dwarf Korean lilac. Lilacs need a long, cold winter to ripen their flower buds, and this territory supplies that. Yellowknife sits in Canadian hardiness zone 1b, a rating from a different system than the USDA zones, so it should never be read as a US zone. That puts the weight on winter hardiness and compact size.

Sensation

Sensation has purple flowers edged with white, which makes it easy to spot among other lilacs. It is rated winter hardy to Zone 3, yet it is described as a poor pick for the colder districts of a northern region. Treat it as a shrub for the milder, more sheltered yards of the territory.

Late-Blooming Hardy Lilac

Some lilacs earn their place through winter hardiness and a late period of bloom, usually the second or third week of June in a far-northern garden. They flower after the common lilac. If a garden centre offers a lilac sold as hardy and late, it deserves a close look.

French Lilacs

French lilacs are selections of the common lilac, Syringa vulgaris, and they are the best known of the group. Hundreds of cultivars exist, in many colors and floret shapes, so you can choose by flower rather than by habit alone. Check the hardiness label on each one before buying.

Dwarf Korean Lilac

Syringa meyeri, the dwarf Korean lilac, is also called the little-leaf lilac. It usually grows about 1.5 m (5 ft) tall and as wide, and it is a profuse bloomer with small violet flowers. Breeders have used it often because it is small and compact, which suits a yard where space is limited.

How to Choose a Lilac for a Northwest Territories Garden

Start with the winter. A lilac that cannot take the cold will die back, and a lilac with no real winter will not set flowers. Then match the shrub to the space you have.

Hot, humid summers are the usual trouble for lilacs elsewhere, and a northern summer is a gentler setting for them. Choose with winter hardiness first, then size, then bloom timing.

French lilacs offer many flower colors and shapes, but check each cultivar’s hardiness and mature size. Look for the hardiest ones and read the tag before you buy.

Which Lilacs Suit Different Parts of Northwest Territories

The territory is large, and spring arrives at different times from one district to the next. The choice of lilac shifts a little with it.

• Yellowknife: The last spring frost falls on average May 25, and frost often comes later than that, so treat the date as the middle of a window. Hardy French lilacs and the dwarf Korean lilac suit a sheltered yard here.
• Inuvik and the northern districts: Spring runs weeks behind Yellowknife, so lean toward the hardiest, latest-blooming lilac you can find. Sensation is the wrong bet in the coldest spots.
• Fort Smith and Hay River: Ask locally which common lilacs have survived, since the Yellowknife reference figures do not describe every community.

Wherever you garden, ask which sites have protected lilacs through local winters.

Lilac Buying Mistakes to Avoid in Northwest Territories

Trusting a Borderline Hardiness Rating

Sensation carries a Zone 3 rating but is still described as a poor fit for colder northern districts. A shrub planted near the edge of its range can die back and flower poorly. Ask for the hardiest cultivar on the bench, and keep it in a sheltered corner.

Pruning at the Wrong Time

A lilac blooms on last year’s wood and sets next year’s flower buds in summer, soon after it flowers. Prune right after the flowers fade, in June or July, and not in late summer, fall or winter, which cuts off the coming spring’s flowers. An overgrown lilac can be cut back hard in late winter, but expect no flowers for a few years afterward.

Ignoring Mature Size

A small pot hides the shrub it will become. A dwarf Korean lilac usually reaches 1.5 m (5 ft) in height and width, and it can occasionally reach 2.4 m (8 ft). Check the tag for the adult size, then leave that much room from walls, walks and windows.

Where to Get Lilac Advice in Northwest Territories

Start with territorial guidance and local growers who know the district’s soil, frost and wind.

• The agriculture services of Northwest Territories Industry, Tourism and Investment can point you to growing information for the territory, so call before planting.
• A local garden centre can tell you which lilacs it has seen survive nearby winters, and spring is a good time to ask.
• A garden society or territorial gardening group offers neighbors’ results, which are worth reading before you buy.

Common Questions

When Do Lilacs Bloom in the Northwest Territories?

Lilacs flower in June, and a few start in late May. Late cultivars open in the second or third week of June. No local extension page covers lilac timing here, so the dates follow the nearest comparable climate; confirm them with a local garden centre, a garden society or a territorial gardening group.

What Is the Difference Between a French Lilac and a Dwarf Korean Lilac?

French lilacs are selections of the common lilac, Syringa vulgaris, and come in hundreds of cultivars. The dwarf Korean lilac, Syringa meyeri, is a separate species that stays compact and covers itself in small violet flowers.

Is a Canadian Hardiness Zone the Same as a USDA Zone?

No. The Canadian system uses seven climate variables, while the USDA system uses one, so the zones do not convert. Yellowknife is zone 1b in the Canadian system, and that number should be read only against Canadian plant ratings.