When to plant crocuses in Elko: 13 September – 15 November

In Elko, crocus: plant from 13 September to about 15 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 Elko: soil, season and weather

Nights then average below 0 °C in November–March; the coldest, January, averages -9.1 °C.

Planting	13 September – 15 November
First autumn frost	13 October
Coldest nights	January, -9.1 °C
Soil back at 1 °C in spring	5 March
Daylight	12:36 on 13 September
Daylight at the winter solstice	9:14

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

Crocus in Elko: 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 Elko 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

All the nearest cities on our list plant crocus later than Elko; the closest date is in Idaho Falls, 1 day later.

City	Distance	Date	Difference
Boise	310 km	27 September – end of December	14 days later
Salt Lake City	324 km	26 September – 23 December	13 days later
Reno	375 km	28 September – end of December	15 days later
Carson City	391 km	22 September – end of December	9 days later
Idaho Falls	425 km	14 September – 14 November	1 day later
Las Vegas	522 km	by 12 November	60 days later

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