When to plant crocuses in Erzurum: 16 September – 20 November

In Erzurum, crocus: plant from 16 September to about 20 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 Erzurum: soil, season and weather

Nights then average below 0 °C in November–March; the coldest, January, averages -10.3 °C.

Planting	16 September – 20 November
First autumn frost	16 October
Coldest nights	January, -10.3 °C
Soil back at 1 °C in spring	12 March
Daylight	12:27 on 16 September
Daylight at the winter solstice	9:20

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

Crocus in Erzurum: 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 Erzurum the average daily temperature stays at 10 °C or lower for about 29 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 Erzurum; the closest date is in Gyumri, 4 days later.

City	Distance	Date	Difference
Trabzon	180 km	by 13 November	58 days later
Batumi	195 km	by 13 November	58 days later
Gyumri	239 km	20 September – 23 November	4 days later
Diyarbakır	240 km	26 October – end of December	40 days later
Van	240 km	29 September – 21 November	13 days later
Yerevan	277 km	3 October – 4 December	17 days later

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