Ipomoea: How to grow successfully in open ground or in pots?

Where to plant Ipomoea?

Ipomoea likes heat, sun and a light, well-drained fertile soil. To thrive, it should be placed somewhere receiving several hours of direct sunlight a day, ideally sheltered from winds that could damage its voluble stems. As it climbs rapidly, it needs a support to cling to: wire mesh, pergola, trellis or window box with canes. In a pot, it will do well if given enough space and a good support to cling to.

Ipomoea is a vigorous plant that needs a support on which to climb.

When to sow Ipomoea?

Ipomoea sowing is done in spring, when temperatures warm up. Under heated cover, sowing can be started as early as April to obtain earlier flowering. Outdoors, wait until frosts have passed, generally from mid-May.

How to sow morning glory?

Under cover

To get a head start, sow morning glory under cover:

• Soak seeds in warm water for 12 to 24 hours to soften their seed coat.
• Fill small pots or alveolate trays with a light, free-draining potting compost.
• Place one seed per pot, pushing it down about 1–2 cm deep.
• Water lightly and keep growing medium moist but not waterlogged.
• Place pots in a bright, warm spot (18–20 °C).
• Plant out in ground when seedlings have 3 or 4 true leaves and temperatures are mild.

You can sow morning glory seeds in pots or alveolate trays and keep them under cover before planting out in ground. (photo : Maja Dumat)

Sowing outdoors

You can also sow morning glory directly outdoors in its final position. Follow this method:

• Wait until frosts have finished, usually after mid-May.
• Soak seeds in warm water for 12 to 24 hours to aid germination.
• Prepare soil by working it lightly and incorporating well-rotted compost to enrich it.
• Sow seeds in small groups of 3–4, spaced 30 cm apart.
• Cover with 2 cm of fine soil
• Water gently to moisten soil without waterlogging.
• Thin out so only the most vigorous seedling remains in each cluster.
• Install a support (trellis, wire mesh, hoop) to guide stem growth.

Morning glory can be sown directly in ground in the garden.

When and how to plant Ipomoea in open ground in the garden?

Ipomoea, being a frost-tender plant, does not tolerate cold. Planting outdoors should be carried out after all risk of frost has passed, i.e. between mid-May and early June depending on region. To ensure success:

• Choose a very sunny position with light, free-draining soil.
• Dig a hole twice the size of the plant’s rootball.
• Place a handful of well-rotted compost in the bottom of the hole.
• Set the plant without burying the collar, then backfill gently.
• Water thoroughly to encourage rooting.
• Install a sturdy support for it to climb (trellis, pergola, wire mesh).

How to plant it in a pot?

In a pot, Ipomoea requires a container at least 30 cm deep with effective drainage. You can also grow it as a hanging plant, for example on your balcony, where its stems will spill nicely over the outside of the pot. Here are steps to plant Ipomoea in a pot :

• Prepare a pot by placing a mix of multi-purpose potting compost and compost in it.
• Gently remove the young Ipomoea plant from its original pot.
• Place it in the centre of the new pot.
• Backfill by adding potting mix all around, then firm lightly.
• Water generously.
• Put in a trellis, stake or taut wires at planting to guide growth.
• Continue to water regularly, especially during hot spells, as the potting mix dries quickly in pots.

You can grow Ipomoea as a hanging plant.

How to care for morning glory?

Ipomoea is an easy plant to grow provided it receives warmth, light and water. Remember to water regularly, especially during hot spells, while avoiding excess that could cause the roots to rot. Be even more vigilant if you grow it in a pot, as the growing medium dries out more quickly. You can apply liquid fertiliser for flowering plants every two to three weeks to favour abundant, prolonged flowering. Remove faded flowers as you see them to stimulate production of new buds. In regions with mild winters, Ipomoea may self-seed, resulting in new flowering the following year.