Greenly Garden
Get the app
EN

When to plant crocuses in Billings: 14 September – 23 November

In Billings, crocus: plant from 14 September to about 23 November.

Bulbs are best planted early in the window: late-planted bulbs may flower later or less well. Late planting works only while the soil can be dug. Mulch after planting.

The date is about two weeks before the average daily temperature here falls below 0 °C (ten years of weather): an estimate, not the day the ground freezes, and a cold spell can freeze it earlier. Sources: Iowa State University Extension, Wisconsin Horticulture Extension, UNH Extension, RHS, how the ground freezes (NRC Canada, CBD-26).

Crocus in Billings: soil, season and weather

Nights then average below 0 °C in November–March; the coldest, February, averages -9.8 °C.

Planting14 September – 23 November
First autumn frost14 October
Coldest nightsFebruary, -9.8 °C
Soil back at 1 °C in spring25 February
Daylight12:39 on 14 September
Daylight at the winter solstice8:40

The same dates in Billings hold for Garlic, Tulip, Daffodil and Hyacinth.

Crocus in Billings: depth, winter cold, pests and pets

Plant Dutch crocuses (Crocus vernus) about 12 cm deep and 9 cm apart; smaller species go 7–10 cm deep (RHS).

In Billings the average daily temperature stays at 10 °C or lower for about 28 weeks a year (our estimate from ten years of monthly weather). For this bulb Wisconsin Horticulture Extension gives a cold period of 15–17 weeks at about 2–10 °C. The winter here gives that in the ground, so the bulbs need no pre-chilling.

Crocuses multiply on their own (they naturalise); in a lawn, hold off mowing until their leaves die back (RHS).

Birds, squirrels and rodents damage crocuses; planting under metal mesh may reduce losses (RHS). Spring crocus gives dogs and cats vomiting and diarrhoea; do not confuse it with autumn crocus (Colchicum), which is very toxic (Pet Poison Helpline).

Sources: RHS, Wisconsin Horticulture Extension, Pet Poison Helpline.

Crocus in nearby cities

1 of the nearest cities share Billings's date.

CityDistanceDateDifference
Helena287 km3 September – 5 November11 days earlier
Idaho Falls377 km14 September – 14 Novembersame day
Missoula441 km6 September – 12 November8 days earlier
Rapid City457 km12 September – 28 November2 days earlier
Regina594 km6 September – 22 October8 days earlier
Cheyenne595 km13 September – 4 December1 day earlier

Where to buy crocus for planting in Billings

Planting stock goes into the ground from 14 September to about 23 November; buy it before that. Within 15 km of Billings OpenStreetMap lists 7 garden centres, 11 farm-supply shops, 3 plant nurseries and 4 markets (collected 20 October 2026).

Places: © OpenStreetMap contributors, ODbL.

Questions

When to plant crocuses in Billings?

In Billings, crocus: plant from 14 September to about 23 November. Bulbs are best planted early in the window: late-planted bulbs may flower later or less well. Late planting works only while the soil can be dug. Mulch after planting.

When is the last spring frost in Billings?

Last spring frost around 25 April, first autumn frost around 14 October.

Other crops in Billings, with their dates