Poinsettia - how we can keep them healthy... and should we bother?

With many of us now nursing sickly-looking plants and wondering what to do with them, horticultural expert and former Poinsettia grower Dan Ori explains how to treat your Poinsettia if you want to keep them.

These are beautiful tropical plants available in a variety of red, pink, white and patterned colourings. For me they are a Christmas must and make a great gift. It is important to highlight that they do have a degree of toxicity so they are to be avoided if you think a pet or child might fancy eating one, also the sap can cause skin and eye irritation.

Firstly there is no shame in treating your Poinsettia as a short use plant, as we do with cut flowers and many annual garden plants. This short use of a month or two in the home is actually the desired outcome of the grower and the convention among most who buy them.

If you are up for the challenge of keeping one past January, these plants can get big; growers normally use a growth inhibitor and this stops working after a few months.

They hate draughts, the best place to grow them at home is a light spot but not in strong sunlight, draught free, and a consistent room temperature above 13C/55F.

As far as watering goes you are more likely to kill these plants by overwatering! Make sure they don’t sit in water, and only water once the top of the compost has dried out; to test if the top of the compost is dry, sink your index finger in the compost down to the knuckle and if you can't feel any moisture water it.

The colour interest is not from flowering, the colourful growth are modified leaves called bracts, for this reason feeds to maintain the colour are different from flowering plant feeds. You can feed monthly with a specific Poinsettia feed or a low nitrogen/high potassium fertiliser.

Cut back hard in April to a healthy leaf or bud. Re-pot in May using a house plant compost or 3 parts John Innes No3 and 1 part horticultural grit.

If you want to fool them into colouring up, they need 12 hours of total darkness for about 8 weeks. So for colour in the summer you have to imitate winter light conditions, let them get a full day of sun then put in a dark cupboard for a day or so, then bring out for a few hours each day until the bracts colour up.