When to plant crocuses in Juneau: 6 September – 12 October

In Juneau, crocus: plant from 6 September to about 12 October.

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 Juneau: soil, season and weather

Nights then average below 0 °C in October–April; the coldest, February, averages -8.9 °C.

Planting	6 September – 12 October
First autumn frost	6 October
Coldest nights	February, -8.9 °C
Soil back at 1 °C in spring	19 May
Daylight	13:39 on 6 September
Daylight at the winter solstice	6:23

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

Crocus in Juneau: 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 Juneau the average daily temperature stays at 10 °C or lower for about 44 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

Around Juneau, Fairbanks is 13 days earlier and Victoria 76 days later.

City	Distance	Date	Difference
Whitehorse	272 km	29 August – 7 October	8 days earlier
Anchorage	923 km	14 September – 18 October	8 days later
Fairbanks	1,008 km	24 August – 2 October	13 days earlier
Yellowknife	1,189 km	4 September – 4 October	2 days earlier
Vancouver	1,244 km	18 October – end of December	42 days later
Victoria	1,316 km	21 November – end of December	76 days later

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