Our secrets to keep cannas flowering all summer long

Plant at the right time

Planting Cannas should be carried out at the right time to allow them to establish themselves properly and ensure their future flowering. Do this in spring, once all risk of frosts has passed, i.e., between the end of March and the end of May, depending on the region.

However, it is perfectly possible to speed up flowering by starting the planting indoors from February, in a frost-free, well-lit location. The Cannas can then be moved outdoors as soon as temperatures are mild enough, gradually acclimatising them.

Similarly, in regions where there is no frost in winter and summers are hot and dry, it is possible to plant in autumn. This will allow the plant to settle in calmly for many months before its first summer.

If you plant several Cannas, ensure a distance of at least 50 to 60 cm between each plant (or more if you choose the largest varieties, such as the Canna ‘Endeavour’ or the giant Canna musaefolia). This will allow them to grow properly and promote their subsequent flowering.

Choose the right exposure

Canna lilies are not difficult to grow, but they have a few requirements to grow well and to flower abundantly.

Firstly, these rhizomatous plants require a warm, sunny exposure. Particularly in the northern Loire region, therefore consider planting them due south, ideally in front of a wall that will reflect sunlight.

Flowering can be damaged by strong gusts of wind. Be sure to choose a fairly sheltered position, protected from prevailing winds.

Canna lilies need a warm, sheltered position in full sun

Feed to support flowering

Cannas are hungry plants, which need soil rich in organic matter to produce their beautiful flowers in warm tones.

At planting time, make sure to amend the soil first with well-decomposed household compost or a suitable fertiliser. Choose a fertiliser rich in potash to support flowering. Conversely, avoid fertilisers rich in nitrogen, which will promote leaf growth at the expense of flowers.

You will find on our site or in-store fertilisers specially designed for flowering plants, which will be perfect for feeding Cannas.

There are two packaging formats:

• the liquid fertiliser to be diluted in irrigation water, which provides a rapid, short-lived effect;
• the solid fertiliser in the form of sticks or granules to mix into the growing medium, which diffuses more slowly but lasts longer.

Apply organic matter in spring, as the plants grow, but also in summer at the onset of flowering.

Remember that, even if Cannas love fertile and deep soils, they do not appreciate substrates that are too heavy (clay). Their soil must indeed be drained to avoid stagnant moisture harmful to their rhizomes. If necessary, mix your garden soil or potting compost with draining elements to lighten it: river sand, clay balls, pozzolana, etc.

Water correctly

In its natural habitat (the tropical and subtropical regions of the Americas), the canna lily grows in wetlands, by rivers or at the edge of forests. It is therefore a plant that loves water and will not tolerate its substrate drying out too much during the summer to flower well.

Keep soil consistently moist — that is, damp but not waterlogged. As soon as the surface looks dry, water generously, ideally with rainwater. Prefer large, infrequent waterings to several small, regular ones.

If you are growing Cannas in pots, you will need to be even more vigilant about the moisture of the growing medium. It will, in fact, tend to dry out much faster than in the ground.

To limit evaporation and keep the soil cool for longer, we recommend installing an organic mulch at the base of your plants.

Maintaining moist soil throughout the summer will promote flowering.

Moist soil in summer promotes a beautiful flowering of Cannas

Prune faded flowers

As the season progresses, think about removing faded flowers to encourage your Cannas to bloom for longer. For this, use a well-sharpened and previously disinfected pruning shear.

Protect these frost-tender plants during winter

In regions with a warm climate, which do not experience frosts or winters that are too wet, Cannas can stay in the ground. They will simply be protected by a thick mulch.

Elsewhere, the rootstocks will need to be dug up in autumn before the first frosts. Store them frost-free in a cool, well-ventilated room. Of course, you can opt for pot culture, which allows you to keep Cannas frost-free through the winter. The young plants can even remain in growth and continue to flower in winter, if you provide them with a location where the temperature is above about 10°C (greenhouse, conservatory)…

Prioritise certain varieties

Smaller varieties tend to bloom more quickly, and thus for longer, than the giant varieties. Under good conditions, you can thus enjoy the exotic charm of their July to November flowers. For example, favour Canna indica ‘Louis Cottin’, as well as the varieties ‘Picasso’, ‘Lucifer’, ‘Firebird’ or also ‘Confetti’.

The Canna ‘Picasso’, like all smaller varieties, will bloom more quickly and for longer