What to sow and plant in September
39 crops on the list have something to do in September at 50.0°. These dates are not a fixed calendar: they are calculated from the estimated last spring frost for this latitude, so they move with your location.
This month normally sits between the last spring frost and the first autumn one, so tender crops can be outside. Heat, water supply and disease pressure become the limits instead of cold.
Sow direct outdoors(9)
Sown where the crop will grow. Soil temperature decides this more than the calendar does, so check the figure on each crop page before sowing.
Plant out(2)
Moved from pots to their final position. Harden plants off over a week first; a tender crop planted into cold soil stalls rather than grows.
Ready to harvest(31)
An approximate window from the sowing dates above. Each crop page carries the physical cue that beats any date.
- 🍅Tomatoes29 Jul – 12 Sept
- 🥔Potatoes3 Aug – 12 Sept
- 🫑Peppers3 Aug – 22 Sept
- 🧅Onions2 Sept – 2 Oct
- 🥬Kale24 Jul – 21 Nov
- 🥦Broccoli24 Jul – 2 Sept
- 🥦Cauliflower3 Aug – 12 Sept
- 🫘Broad beans3 Aug – 12 Sept
- 🎃Pumpkins13 Aug – 22 Sept
- 🌽Sweetcorn3 Aug – 2 Sept
- 🍆Aubergines23 Aug – 2 Oct
- 🥬Swiss chard29 Jun – 21 Nov
- 🍐Pear trees22 Sept – 11 Nov
- 🍑Plums23 Aug – 17 Oct
- 🍒Cherries2 Sept – 1 Nov
- 🍑Peaches2 Sept – 1 Nov
- 🍓Strawberries4 Jul – 2 Sept
- 🫐Raspberries23 Aug – 1 Nov
- 🫐Blackberries22 Sept – 21 Nov
- 🫐Blackcurrants23 Aug – 12 Oct
- 🍒Redcurrants23 Aug – 7 Oct
- 🫐Gooseberries13 Aug – 2 Oct
- 🫐Blueberries2 Sept – 1 Nov
- 🌿Basil24 Jun – 2 Sept
- 🌿Parsley4 Jul – 2 Sept
- 🌿Chives4 Jul – 21 Nov
- 🌸Dahlias3 Aug – 12 Oct
- 🌻Sunflowers24 Jul – 22 Sept
- 🌼Marigolds24 Jun – 2 Oct
- 🌺Lilies3 Aug – 2 Oct
- 🌸Sweet peas24 Jul – 2 Oct
What to watch for in September
Problems the database lists for this part of the year, most damaging first. Each one calculates live risk for your location on its own page.