Q: Poinsettias are my favorite holiday plant — but they never seem to last as long as in years before. Can you suggest some help? Through the years, I’ve heard they are quite poisonous — is that really true?
A: About the health of a poinsettia: When you buy any plant, not just poinsettias, take time to look at the leaves carefully. White flies, which congregate on the underside of the leaves, are highly contagious to your other houseplants. White flies are visitors you don’t need in your house over the holidays.
Keep the plant out of drafts — and this means special concerns when transporting a plant home or to a friend on a cold day. Warm the car before putting the plant in it — poinsettias that have been exposed to very cold temperature will turn black on the edges of the leaves.
Water the plant very well when the top layer of soil is dry to the touch, and keep the plant in strong, filtered light. It’s always a temptation to brighten up a dark corner with this cheerful plant, but please move it back to a bright window after a day or two — or put a grow-light on it — or you may lose an expensive plant.
The red poinsettias seem to live longest, but the pink and the white and peach, even striped colors are in the market and offer a pleasant change from the traditional reds.
Now on the subject of how toxic this plant is. All of the members of this plant family euphorbia, which includes crown of thorns and milk bush (sometimes called pencil tree), have a milky sap in the stem that can be irritating to the skin. If large enough amounts of petals, leaves or roots are eaten any time, they can cause swelling of the lips and throat, as well as gastric irritation, like vomiting. If you think that the plant or plant parts have been eaten, call a doctor or vet — take the patient and a piece of the plant — and get emergency care.