Things to do this week:

* Plant cinerarias along coast. One of the truest blue flowers for the Southern California garden is the cineraria, Senecio hybridus, a winter- or spring-blooming bedding plant available at nurseries now. You can plant them right away in frost-free areas near the coast, but hold off where frosts are likely as this bedding plant is unusually tender and will burn at the mere hint of real cold. Inland gardeners usually plant in late February or early March.

* There are short kinds and tall, although the big clusters of flowers on both are nearly identical. Colors include vibrant true blues as well as purples, magenta and a white. Cinerarias seem to do best in open shade that is not too dark and with ordinary irrigation. They also grow well in pots.

Let them go to seed and you may get a return crop of tall, airy, nearly wild plants that are even prettier than the commercial varieties. These grow wild in some coastal gardens from San Diego to Santa Cruz.

* Unwrap poinsettias. Plastic or paper sleeves used to ship poinsettias should be removed immediately or they will cause the plants to yellow and drop their leaves. Sitting too long in a sleeve is considered the No. 1 cause of leaf drop, and some even recommend not buying poinsettias that are still wrapped snugly in their sleeves.

* Shop for living Christmas trees. The selection of living trees is greatest now, but if you buy one, don’t bring it indoors quite yet. Keep it as outdoor decoration until Christmas week. Trees will easily last indoors for a week with no damage, usually even two, but no longer or the needles will fall off. Be careful not to over-water trees and make sure the containers have drainage holes (and are not wrapped in foil). When you do bring them indoors, set the pots in a waterproof saucer and empty excess water after watering. Good choices for living trees that will keep for several years in a pot include droopy, gray-needled deodar cedar, Aleppo pines and sequoias. Decorate them with berries, popcorn, seeds and cookies, and you can simply leave them outside after the holidays and birds will pack away all the “ornaments!”