How to grow Morning Glory (Heavenly Blue)

Ipomoea tricolor

🌸 Flower 🌱 Grown each year

Huge, sky-blue trumpets that open every morning on a fast climbing vine. The seeds are poisonous — keep away from children.

At a glance: Sow mid March to early April.

When to sow, plant and harvest

JanFebMarAprMayJunJulAugSepOctNovDec

Sow indoors

Plant

Flowers

Timed for a typical UK garden (last frost mid-April). The app uses your own town's frost dates.

Mid March – early April · 5 weeks before the last spring frost
Sow Seeds Indoors
Sow in trays or modules of seed compost on a warm windowsill or in a propagator. Nick or soak the hard seeds overnight, then sow 1 cm deep, one per pot, at 20°C.
7–21 days after “Sow Seeds Indoors” · Mid March – early April
Check Germination
Seedlings should appear in 7–21 days. Keep the soil moist. If sown outdoors, thin them to 30 cm apart once they have two true leaves.
14–21 days after “Check Germination” · Early April
Pot On Seedlings
When seedlings have two true leaves, move each into its own small pot or module, holding them by a leaf, not the stem.
Late April · 11 days after the last spring frost
Harden Off
Stand plants outside by day and bring them in at night for 7–10 days so they get used to outdoor conditions.
Early May – early June · 3 weeks after the last spring frost
Plant Out
Plant out 30 cm apart once frosts are over. Water in well.
14 days after “Plant Out” · Mid May
Add a Climbing Frame
Give it netting, a trellis or a wigwam of canes and twist the shoots on.
69–99 days after “Check Germination” · Late May – late June
First Flowers
Take a photo for your journal!
Mid October – early November · around the first autumn frost
Clear or Collect Seed
When frost blackens the plants, pull them up for the compost heap. Leave a few seedheads first if you want to save seed.