About Agapanthus

If you are planting your Agapanthus in the garden, ideally plant in the spring once the soil is warm. Choose a sunny, well drained position. Good soil preparation and addition of organic matter will help it to grow well. If your soil is heavy, add extra grit or bark to aid drainage. 

Plant small growing Agapanthus 30 cm apart, larger varieties 60 cm apart. Water well.

Agapanthus grow happily in pots; indeed, evergreen Agapanthus are often best kept in pots so that they can be moved for the winter. Pot in a John Innes no.3 or equivalent, with 2 parts compost and 1 part grit or bark to improve drainage. 

There is a myth that Agapanthus like to be pot bound. Certainly, if they are in too large a pot, they put on lots of foliage growth at the expense of flowers. However, they are hungry feeders and a pot full of root leaves no room for nutrients or water. So a pot a couple of sizes up is ideal.

Place your pot in a sunny position.

Feed about once a fortnight through the season, from when the leaves appear until after flowering, with a high potash feed (such as tomato feed or our own Algernon’s Amazing Agapanthus Accelerant). Water those in pots when they are dry.

Flowers can be removed once over, left for architectural interest, or dried and sprayed for indoor decoration.

Many deciduous Agapanthus are fairly hardy, but if in doubt or particularly cold weather is forecast, cover with a thick mulch of bark or straw, or fleece.

Place pots in a frost-free environment over the winter, where they will not get waterlogged. If your pots are too heavy to move, wrap them with fleece or bubble wrap. If evergreen Agapanthus need to be in the ground, try to keep close to a house wall, ideally south or west facing where they will stay warmer and put a thick mulch of straw or fleece around the crown.

Agapanthus in the garden will need splitting every 4-5 years. Tackle this job in the spring, just as you can see the shoots, or it can be done immediately after flowering. Have a hearty breakfast, dig around the edges to loosen the roots, then simply (ha!) put two forks back–to–back into the centre of the plant and force apart. The cut edges of Agapanthus bleed, so do not pot the pieces up immediately, but leave overnight for the wound to heal. We cover the roots themselves to prevent them drying out. Then replant or pot up.

If your Agapanthus isn’t flowering well, check the following:

• Is it in enough sun?
• Does it need feeding?
• Was it frosted last winter?
• Does it need dividing?
• Is it too young?
• Is it a poor flowering variety?