Perennial Flower

When to Plant Daylilies in New Hampshire

Nearly indestructible perennials with stunning trumpet-shaped blooms. Each flower lasts just one day, but the show goes on for weeks.

The Short Answer

In New Hampshire, plant daylilies based on your regional frost dates. Northern New Hampshire has a last frost around May 20 - Jun 5, while Southern New Hampshire sees frost end around May 1 - May 20. Short growing season especially in north. Cold winters. Cool summers. Hardy varieties important.

New Hampshire Frost Dates

Your planting dates depend on which part of New Hampshire you're in. Here are the frost date ranges by region:

Region	Zones	Last Frost (Spring)	First Frost (Fall)
Northern New Hampshire	3b, 4a, 4b	May 20 - Jun 5	Sep 10 - Sep 25
Southern New Hampshire	5a, 5b, 6a	May 1 - May 20	Sep 25 - Oct 10

Daylilies Planting Schedule for New Hampshire

Northern New Hampshire (Zones 3b, 4a, 4b)

Average last frost: May 20 - Jun 5 · Average first frost: Sep 10 - Sep 25

Transplant Outside

0 wks after frost

Southern New Hampshire (Zones 5a, 5b, 6a)

Average last frost: May 1 - May 20 · Average first frost: Sep 25 - Oct 10

Transplant Outside

0 wks after frost

Growing Daylilies in New Hampshire

Daylilies in New Hampshire's Climate

Daylilies are bombproof perennials for cold climates. They survive harsh winters, tolerate poor soil, and bloom reliably through moderate summers. Choose dormant varieties for the coldest zones — they go completely dormant in winter and emerge vigorously each spring. Stella de Oro reblooms from June through frost.

Soil Considerations for New Hampshire

Rocky, acidic New England soils. Glacial deposits. Granite bedrock. Raised beds essential in many areas.

New Hampshire Climate & Growing Season

Short growing season especially in north. Cold winters. Cool summers. Hardy varieties important. Daylilies can handle frost well, which is an advantage in New Hampshire's climate. You can push planting dates earlier in spring and extend into fall.

Growing season length varies across New Hampshire: Northern New Hampshire (3b, 4a, 4b) has a last frost around May 20 - Jun 5, while Southern New Hampshire (5a, 5b, 6a) sees frost end around May 1 - May 20. This difference matters for daylilies — adjust your planting dates to match your specific region.

Growing Tips

Plant bare-root or divisions in spring or fall. Divide clumps every 3-4 years to maintain vigor. Deadhead to keep gardens tidy.

Companion Planting

Plant daylilies alongside these companions for better growth:

Coneflowers Black Eyed Susans

The Bottom Line

Daylilies can be grown successfully across New Hampshire, but your exact planting dates depend on which region you're in. Northern New Hampshire gardeners should plan around a May 20 - Jun 5 last frost, while those in Southern New Hampshire can typically plant earlier. For exact dates based on your zip code, use our free planting date finder.

Note: All dates are based on NOAA 30-year Climate Normals and represent historical averages, not predictions for any specific year. Always check your local weather forecast before planting frost-sensitive crops. Learn about our data sources.

Last reviewed: March 29, 2026