Safe to Plant

Marrow · Yaroslavl, Yaroslavl Oblast, Russia

When to plant marrows in Yaroslavl

Main outdoor window

5-26 Jun

The window this page is built around.

Timed from last spring frost

8 May

In Yaroslavl, on your chosen risk.

Ready to pick

1 Aug - 31 Oct

If you plant at the start of the window.

The average last frost. Half of all years are later than this.

Held back by cold soil. Frost is finished by about 22 May here, but marrows will not get going until the soil reaches 15°C (59°F), and in Yaroslavl that is around 5 June. The dates above use the later of the two, because sowing into cold soil rots seed rather than gaining you time.

Step by step in Yaroslavl

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

17 Apr - 8 May

Three weeks before your last frost, under cover or on a windowsill.

Sow direct

5-26 Jun

Held back until the soil is warm enough for this crop. The frost date on its own would say 22 May, which is too cold for it to start.

Plant out

5-26 Jun

Held back until the soil is warm enough for this crop. The frost date on its own would say 22 May, which is too cold for it to start.

Harvest

1 Aug - 31 Oct

Frost tolerance
Tender
Damaged below
0°C (32°F)
Days to maturity
60–80
Min soil temp
15°C (59°F)
Spacing
90 cm
Sowing depth
25 mm (1 in)
Sun
Full

Marrows through the year

Against the frost risk in Yaroslavl

Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Frost risk Start indoors Sow direct Plant out Harvest Today

Why these dates

Sow two weeks after the last frost. Let two or three fruits swell per plant and remove the rest, since a plant carrying everything ripens nothing well.

Killed at 0C. Cut and bring the fruit under cover before the first autumn frost, which softens the skin and ends any chance of storing it.

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. Marrows are timed from 3 weeks before that frost for an indoor start, with planting out 2 weeks after it, and this page simply resolves those offsets against the frost date computed for Yaroslavl.

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 151 days, against 60 to 80 days to maturity for this crop counted from sowing. That margin is what decides whether a late sowing is worth attempting.

See every crop timed for Yaroslavl →

Growing marrows in Yaroslavl

When should I plant marrows in Yaroslavl?

Aim for 5-26 Jun in an average year. If you would rather not gamble on the weather, wait until 5-26 Jun - by then frost has finished in nine years out of ten.

Can I plant marrows earlier in Yaroslavl?

Frost is finished by about 22 May, but the soil is still too cold. Marrows will not start until it reaches 15°C (59°F), and here that is around 5 Jun. Going in earlier usually means seed that rots or transplants that sit and sulk, and a later sowing catches them up.

When will marrows be ready to harvest in Yaroslavl?

Expect to start picking around 1 Aug - 31 Oct, based on 60 to 80 days to maturity from the planting date calculated for this location.

How much frost will marrows tolerate?

Killed at 0C. Cut and bring the fruit under cover before the first autumn frost, which softens the skin and ends any chance of storing it.