Best Lilacs for Wyoming

A lilac in full bloom against a Wyoming spring sky is a sight that tells you the shrub is at home. Cold winters are exactly what it wants.

Best Lilacs to Grow in Wyoming

Wyoming suits lilacs well, because they need a cold winter rest to mature their flower buds and the state delivers one. Common lilac, hyacinthiflora hybrids, Preston hybrids and tree lilac all fit, as long as you match bloom time to your frost risk. Hardiness zones here run from 3a to 6a (USDA system), so check the label on each cultivar against your own site.

Common Lilac

Syringa vulgaris, also sold as French hybrid lilac, is noted for big blooms and strong fragrance. It is one of the hardiest shrubs and adapts to almost any soil and watering condition. Hundreds of cultivars give you white, deep purple, wine red and light pink.

Give it room. The common lilac grows 10 to 15 feet tall with a spread of 6 to 12 feet, so plant it where it can reach that size.

Hyacinthiflora Hybrids

Syringa × hyacinthiflora, the early flowering lilac, looks like a French hybrid but blooms seven to 14 days earlier. The shrubs themselves are very hardy. Because they open early, plant them only where May frosts are less frequent.

Preston Hybrids

Preston hybrids generally flower more reliably in colder, windy areas than early-blooming hyacinthiflora types. That makes them a sensible pick for an exposed Wyoming yard where late frosts and wind are the norm, such as open ground on the plains.

Tree Lilac

Syringa reticulata, the tree lilac, is a water-wise option for a dry-climate garden. Its June blooms close out the lilac season, which helps if you want color after the common lilacs fade.

Own-Root Lilacs

Lilacs on their own roots are far more hardy than grafted lilacs. In a state with winters this cold, ask whether a plant is grafted before you buy. Mixing several species can keep lilacs in bloom for at least six weeks, with flowering running May into June.

How to Choose a Lilac for a Wyoming Garden

Start with what your yard throws at a shrub: how hard winter hits, how much time you have, and how much space is free. Lilacs adapt to zones 3, 4, 5 and milder parts of zone 2, and they like sunny sites with good air circulation.

Zones differ across the state, so check your own zone on the USDA map before you commit to a variety.

A lilac that needs a cold rest rarely lacks it here, so cold itself is seldom the limit. Late frost is the bigger worry, since frost can arrive in any month at higher elevations.

Which Lilacs Suit Different Parts of Wyoming

Elevation shapes the choice more than anything else, because it decides how often a late frost reaches open buds.

• Cheyenne and the southeast plains: For Cheyenne, the last spring freeze typically falls between May 7 and May 18; other parts of southeastern Wyoming differ. Keep early bloomers in sheltered spots, while Preston hybrids suit exposed, windy sites.
• Laramie and the high Laramie Plain: At this elevation frost is possible in any month, so favor later bloomers and own-root plants over early types.
• Casper and the central basins: Dry, windy and cold in winter, which favors tough, hardy common lilacs and Preston hybrids.
• Jackson Hole and the mountain valleys: Short seasons and late frosts call for sheltered spots and later-opening lilacs, such as tree lilac.

Wherever you are, a spot with sun and moving air beats a frost pocket.

Lilac Buying Mistakes to Avoid in Wyoming

Buying a Grafted Plant

Grafted lilacs are less hardy than own-root ones, and a hard winter can kill the top above the graft. The plant then suckers from the rootstock, not the variety you paid for. Look for own-root plants.

Planting an Early Bloomer in a Frosty Spot

Hyacinthiflora hybrids open seven to 14 days ahead of the French types. In a yard where May frosts are common, that early head start can cost you the flowers. Choose Preston hybrids or common lilac there, and save early types for sheltered, warmer corners.

Ignoring Adult Size

A small pot hides a shrub that reaches 10 to 15 feet tall. Crowded against a house or walk, it demands constant cutting. Prune right after flowering in June, when next year’s buds begin to form; if flowering runs late, July can also work. Keep blooms near nose height. An overgrown plant can be cut hard in March or April, though it will not flower for a few years afterward.

Where to Get Lilac Advice in Wyoming

For local questions on varieties, frost and pruning, University of Wyoming Extension [link: https://www.uwyo.edu/uwe/] is the place to start, and your county office can speak to conditions in your own valley or plain.

• The state extension site carries publications on shrubs and cold-climate planting, handy before you shop in spring.
• Your county extension office answers questions about your soil and site, and is worth a visit in late winter before you plan any hard cut.
• Photos of a struggling shrub help staff diagnose it, ideally taken in May or June when the plant should be in bloom.

Common Questions

How Long Do Lilacs Bloom in Wyoming?

Blooms run through May and June. Planting several species stretches the show to at least six weeks, with early, common and tree lilacs taking turns.

Do Lilacs Like Full Sun?

Yes. They thrive in sunny sites with good air circulation, which also helps in a state with wind and cool nights.

Can Lilacs Grow in a Hot, Humid Yard?

They struggle there. Lilacs rely on a cold winter rest to mature their buds, so they do their best where winters are cold.

Sources : u.osu.edu