When to Plant Fall Flowers in London, ON – 2026
Published: April 27, 2026
London is in Canadian Zone 6a (southwestern Ontario temperate). Last spring frost averages May 3; first fall frost October 20; the growing season runs about 170 frost-free days. Plant fall flowers in London from spring planting (after victoria day) for fall bloom; nursery mums in august-september..
Fall Flowers Planting Window for London, ON
Plant fall-blooming mums, asters, and sedums in spring or early summer for fall bloom. Fall-planted pansies and ornamental kale provide color into November in Zones 6+. Plant bulbs for next fall: dahlias in spring; tulips in fall.
For London, ON specifically, the recommended planting window is Spring planting (after Victoria Day) for fall bloom; nursery mums in August-September.. London has 150-170 frost-free days — adequate for most warm-season crops when transplants go in by late May. The region's rich soils support heavy feeders like tomatoes and brassicas with minimal amendment.
Hardy mums (Chrysanthemum) and asters are reliably hardy to Zone 4 with proper fall preparation — choose varieties bred for Canadian winters. Pot mums sold at Canadian Tire in September are often NOT cold-hardy and should be treated as annuals.
Best Fall Flowers Varieties for London, ON
For London, ON (Canadian Zone 6a), choose varieties rated for your zone or one zone colder for reliable winter survival. The Canadian-bred or tested varieties below perform well in Ontario conditions.
Bred for Canadian Prairie winters. The most reliable mums for Calgary, Edmonton, Saskatoon, Regina, Winnipeg.
Hybrid Korean × hardy mums. Reliable Prairie performance with longer bloom period than standard hardy mums.
Native Canadian fall-blooming aster. Reliable to Saskatoon. Strong pollinator value.
Drought-tolerant succulent perennial. Pink-bronze blooms in September. Excellent across all Canadian zones.
Cool-season annuals planted in late summer for fall colour. Continue blooming through October frost in Ontario and BC.
How to Plant Fall Flowers in London
Sow method: transplant (summer planting for fall bloom). The steps below adapt the general planting advice for London, ON's climate and timing.
- →Plant fall-blooming perennials (mums, asters, sedums) in spring (April through June) for established root systems before fall bloom.
- →Plant fall-blooming bulbs (saffron crocus, autumn crocus, fall-blooming species cyclamen) in summer (July through August).
- →Plant cool-season annuals (pansies, ornamental kale) in late summer through early fall for immediate cool-weather color.
- →Pinch growing tips of mums in early summer to encourage bushier growth and more fall blooms.
- →Choose full sun (6+ hours) for mums, asters, and sedums; part shade for pansies in Zone 7+.
- →Water consistently during establishment; once established, fall perennials are drought-tolerant.
Frequently Asked Questions about Fall Flowers in London, ON
When can I plant fall flowers in London?
Plant fall flowers in London from spring planting (after victoria day) for fall bloom; nursery mums in august-september. based on the city's Canadian Zone 6a. Last spring frost: May 3; first fall frost: October 20; frost-free growing season: 170 days.
What Canadian zone is London?
London is in Canadian Zone 6a (USDA equivalent 5b). The climate is southwestern ontario temperate. London has 150-170 frost-free days — adequate for most warm-season crops when transplants go in by late May. The region's rich soils support heavy feeders like tomatoes and brassicas with minimal amendment.
Are fall flowers winter-hardy in London?
Hardy mums (Chrysanthemum) and asters are reliably hardy to Zone 4 with proper fall preparation — choose varieties bred for Canadian winters. Pot mums sold at Canadian Tire in September are often NOT cold-hardy and should be treated as annuals.