Create your calendar

Growing season

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 3 Sep
Daylight
10+ h
14+ h
10+ h
8 Mar
6 Apr
7 Sep
6 Oct
212 days
Frost-free
10% frost-free
1 Jun
31 Aug
90% frost risk
91 days
Effective
1 Jun
31 Aug
91 days

The growing season in Saariselka is approximately 91 days and is limited by frost.

Last spring frost

The last spring frost normally occurs on 1 Jun in Saariselka. At the earliest, the last frost is over around 22 May and at the latest around 13 Jun.

Frost-free probabilityFrost-free prob. Date Grower's risk level Explanation
10% 22 May High risk Frost 9 out of 10 years after this date
25% 24 May Frost 3 out of 4 years after this date
50% 1 Jun Normal risk Frost every other year after this date
75% 10 Jun Frost 1 out of 4 years after this date
90% 13 Jun Low risk Frost 1 out of 10 years after this date
Growing is often planned around the date when there is a 50% probability that the last spring frost has occurred. In Saariselka that is 1 Jun. If you want lower frost risk, choose 75% or 90%, i.e. a later date.

First autumn frost

The first autumn frost normally occurs on 31 Aug in Saariselka. At the earliest, frost can arrive around 3 Aug and at the latest around 24 Sep.

Frost probabilityFrost prob. Date Grower's risk level Explanation
10% 3 Aug Low risk Frost 1 out of 10 years on or before this date
25% 27 Aug Frost 1 out of 4 years on or before this date
50% 31 Aug Normal risk Frost every other year on or before this date
75% 15 Sep Frost 3 out of 4 years on or before this date
90% 24 Sep High risk Frost 9 out of 10 years on or before this date
Growing is often planned around the date when there is a 50% probability that the first autumn frost has occurred. In Saariselka that is 31 Aug. If you want lower frost risk, choose 10% or 25%, i.e. an earlier date.

Daylight & Persephone Period

Plants need at least 10 hours of daylight to grow actively. The period with under 10 h is called the Persephone period.

From To Number of days
Daylight over 10 h 8 Mar 6 Oct 212
Persephone period 7 Oct 7 Mar 153
Plan the year's last sowing of cold-hardy plants in Saariselka so they are approximately 75% mature by 7 Oct when daylight drops below 10 h and growth starts to slow.

Daylight periods

Long-day plants like lettuce, spinach and coriander bolt when daylight gets too long. Plan sowing and harvest during periods when daylight is shorter (10-14 h). Early spring or late summer sowing gives the best results.

Season Light Period Days Advice
Shorter daylight 10-14 h 8 Mar – 5 Apr 29 Grow long-day plants like spinach, lettuce and coriander.
Longer daylight 14+ h 6 Apr – 6 Sep 154 High risk of bolting
Shorter daylight 10-14 h 7 Sep – 6 Oct 30 Grow long-day plants