Five things to do in the garden this week:
1. Your roses may have finally stopped blooming, but the ground around them need not be bare. There are many ground covers compatible with roses that you might consider planting at this time. Hi-Ho Silver and Silver King thyme (Thymus argenteus) have lemon-scented green leaves with silver margins, and Silver King shows off contrasting red stems as well; lamb’s ears (Stachys byzantina) is a tactile sensation of fuzzy, silver-gray foliage, but you will want to make sure your roses are on a drip system since overhead irrigation may cause fungus on lamb’s ears; Serbian bellflower (Campanula poscharskyana) has delicate bell-shaped mauve blooms; catmint (Nepeta x faassenii) is a sterile hybrid whose mass of lavender-blue flowers in winter do not require dead-heading. Note: dead-heading of flowers is done to prevent seed formation since that process demands plant resources that would otherwise be channeled into the development of more flowers. Thus, on sterile plants, where seeds do not form, flowering continues unabated even when older flowers are still in place.
2. Here are a few pointers on pruning of popular perennials that require radical cutting back at this time: Matilija poppy (Romenya coulteri), cut back to the ground; California fuschia (Epilobium canum), cut back to within six inches of the ground; butterfly bush (Buddleia spp.), cut back to a height of three feet; Mexican sage (Salvia leucantha), cut back to a height of two feet; lion’s tail (Leonotis leonurus) and Jerusalem sage (Phlomis fruticose), cut back to a height of 18 inches; Mexican evening primrose (Oenothera speciosa), cut down to the ground.
3. Certain cymbidium orchid varieties start blooming this month, although some will not bloom until the spring, and some bloom all year long. These are among the easiest orchids to grow as they do well outdoors in containers throughout Southern California except where hard freezes may occur, although they absolutely require a dose of autumn cold in order to bloom at all. I once asked a gardener who grew gorgeous cymbidiums about their care and was told: “All I do is water them.” Many orchid species, and cymbidiums in particular, flower at their maximum potential when crowded. In the case of cymbidiums, roots can be growing over the side of the pot or through drainage holes and continue to bloom heavily for many years.
4. Yes, you can grow raspberries in Southern California thanks to varieties that will flower and fruit where winters are mild. In fact, the Kokanee variety requires no winter chill at all in order to produce a crop. Fruit on these subtropical raspberries may develop in all four seasons. As for maintenance, prune canes back to the ground now. When growth resumes in the spring, apply a balanced fertilizer such as 10-10-10. Raspberries are sensitive to hot sun so grow them where they get either morning sun or filtered afternoon sun.
5. If blue and white are your preferred colors, sow seeds of baby blue eyes (Nemophila menziesii), a California native, and white sweet alyssum (Lobularia maritima) in your flower beds or around your woody perennials. These plants will give you three or four crops of flowers a year as they self-sow with alacrity. Both grow no more than 12 inches tall. When a crop begins to decline, simply pull it out; the seeds left behind should begin to sprout in a few weeks.
You are invited to send questions or comments about any plant, or about any gardening practice or problem, to [email protected].
