Sweet pea · Kolomna, Moscow Oblast, Russia
When to sow sweet peas in Kolomna
Main outdoor window
20 Apr - 11 May
The window this page is built around.
Timed from last spring frost
3 May
In Kolomna, on your chosen risk.
Ready to pick
19 Jul - 8 Aug
If you plant at the start of the window.
The average last frost. Half of all years are later than this.
Step by step in Kolomna
Each window is a range, not a single day. Earlier in the range buys you a longer season; later in it buys you a safer one.
Start indoors
22 Feb - 15 Mar
Ten weeks before your last frost, under cover or on a windowsill.
Sow direct
20 Apr - 11 May
Held back until the soil is warm enough for this crop. The frost date on its own would say 22 Mar, which is too cold for it to start.
Plant out
20 Apr - 11 May
Held back until the soil is warm enough for this crop. The frost date on its own would say 5 Apr, which is too cold for it to start.
In flower
19 Jul - 8 Aug
Sweet peas through the year
Against the frost risk in Kolomna
Why these dates
Sow in autumn and overwinter in a cold frame in zone 6 and warmer, or start ten weeks before last frost. Pinch at four true leaves.
Young plants take -8C and benefit from the cold. This is a flower where autumn sowing genuinely doubles the season.
Seed packets and extension guides express timing as weeks either side of the last spring frost, because that is the only reference point that travels. Sweet peas are timed from 10 weeks before that frost for an indoor start, with planting out 4 weeks before it, and this page simply resolves those offsets against the frost date computed for Kolomna.
With one correction, which is the note at the top of the page: the offset alone would put this crop in soil that is still too cold for it. Where the frost date and the soil temperature disagree, the dates here follow the soil, because a seed in cold ground either rots or waits, and a sowing made a fortnight later usually overtakes it.
The median frost-free season here is 157 days, against 90 to 110 days to first flower for this crop counted from sowing. That margin is what decides whether a late sowing is worth attempting.
Nearby
Sweet peas in places close by
Growing sweet peas in Kolomna
When should I plant sweet peas in Kolomna?
Aim for 20 Apr - 11 May in an average year. If you would rather not gamble on the weather, wait until 20 Apr - 11 May - by then frost has finished in nine years out of ten.
Can I plant sweet peas earlier in Kolomna?
Frost is finished by about 22 Mar, but the soil is still too cold. Sweet peas will not start until it reaches 7°C (44.6°F), and here that is around 20 Apr. Going in earlier usually means seed that rots or transplants that sit and sulk, and a later sowing catches them up.
When will sweet peas be ready to harvest in Kolomna?
Expect to start picking around 19 Jul - 8 Aug, based on 90 to 110 days to maturity from the planting date calculated for this location.
How much frost will sweet peas tolerate?
Young plants take -8C and benefit from the cold. This is a flower where autumn sowing genuinely doubles the season.