Colocasia/Alocasia FAQ

What are Colocasias and Alocasias?

They’re tuberous perennials, grown in the UK for their huge Jungle foliage, with some species capable of reaching enormous proportions in a single season. This of course is very much dependant on the summer weather – they love warm and humid conditions so if you want to grow these very special plants pray for a summer heat wave with plenty of rain.

Are they hardy?

Definitely not. Most come from tropical regions and cannot tolerate more than a touch of frost.

How big and how fast will they grow?

A tiny plant is capable of growing in to a monster specimen up to 1.5m tall, depending on the species.

Will they grow in pots?

Yes – they grow fine in pots. The key is not to over pot them. Pot up into a slightly larger pot regularly though the growing season.

What’s the best position and soil type for Colocasias and Alocasias?

A sheltered position (those enormous leaves can tear in exposed positions) in part shade is ideal. Avoid strong afternoon sun. They appreciate a deep, rich, moist soil with lots of organic matter.

How much food and water should I give them?

Plenty. Lots of feed during the growing season and lavish them with water. Feed with a high nitrogen liquid feed to promote leaf growth. This is the key to successful cultivation.

What do I do with them in the winter?

Lift them from the ground before the first severe frosts – usually the end of October. Cut all but the newest leaf off and shake off most of the soil. Cram them in to the smallest pot possible. They hate sitting in lots of compost in winter. Treat pot grown specimens in the same way. Store them over winter in a greenhouse or conservatory heated to a minimum of 5 degrees centigrade and keep the compost barely moist.

Isn’t that a lot of trouble to go to?

We don’t think so. For a plant that gives such a huge impact in the garden throughout the summer and early autumn we think they’re worth it, and during winter, because they’re cut back they take up very little space in the greenhouse.

When can I plant them outside?

Don’t be tempted to plant them out until the end of May/beginning of June. A late frost, although not fatal will set them back considerably.

I’ve heard they can be grown as pond marginals. Is this correct?

Not for Alocasias but certainly some species of Colocasia grow wonderfully well in water. Ask us which ones.