How to get a poinsettia to turn red
Most people love having poinsettias around the house during the holiday season. And why not? They’re very festive, gorgeous, and come in a myriad of colours, from deep red to all shades of pink, cream and even with speckles! The problem is when January comes around and you are left with a sad looking Poinsettia which has lost half of its leaves. You still decided to keep it though, only to find out that when the leaves grow back, they grow back green. Oh no!
Without even attempting to get it to turn red, taking care of Poinsettias is already a challenge. These finnicky gals are native from Mexico, and come from the Euphorbiaceae family, the same family as the African milk cactus, for example. In their natural habitat, they can grow to become large woody shrubs.
They are very susceptible to cold weather, and by cold we mean anything under 14°C. They absolutely despise drafts and sudden changes of temperature. This is very likely why your Poinsettia has been losing leaves since your acquired it. They’re kept in supermarkets or garden centres where the temperatures are cold and changeable, and by the time they reach your home the damage is already done. Even the trip from the shop to your house can damage them. They are that delicate!
The best location you can give a poinsettia is a warm, draft free spot by a south or west facing window where it can bask in indirect light at least half of the day. Don’t place it on your kitchen table, or a spot that sees foot traffic and movement, they just don’t like to be disturbed!
And now onto the more interesting part… how to produce the coloration the following winter season!
If you’re up for the challenge and have not thrown it out yet, you can prune it back to 10 cm stems in April and keep it at a stable temperature of 14°C. You can feed it with half the recommended dose of a well-balanced liquid fertiliser from the beginning of March, every 4-6 weeks.
In May, repot your poinsettia using a mix of perlite, bark and loamy potting soil. If you can add some horticultural sand to the mix, all the better. Wait at least 6 weeks to fertilise again, as the new soil will already have all the nutrients needed. keep it in a bright spot at a temperature of about 18-20°C until mid October.
Here comes the fun part! The key to Poinsettias flowering and turning red is darkness. In their natural habitat, they are in complete darkness once the day ends, but at home or in the city, daytime is lengthened by artificial lighting. If you want to mimic the natural conditions in which Poinsettias live, you’ll have to place it in a dark spot (i.e. a cupboard) for 12 hours a day, for somewhere between 6 to 8 weeks. If you want to display your Poinsettia right at the beginning of December, you’ll have to start the process in early October. Make sure the place you put it does not get below 14°c, is in complete darkness and has no draft!
Once the 12 hours have passed, take the plant back to its original spot and repeat!
Getting poinsettias to turn red again is a true challenge indeed and takes lots of dedication, but hey, if you manage to do it, the reward is sweet!
Do you have any other tips to care for Poinsettias and achieve the coloration? Let us know in the comments below!