Dig In!

This means that right now is the time to make plans to fill those gaps in your garden by planting new plants or moving existing plants. Before you buy and dig, think about the conditions in your garden (such as how much sun it gets and the type of soil); and make sure that the plant you bring home or want to move will do well in its new home. The phrase, "Grow where you are planted” is great inspiration for people, but it is pretty useless when it comes to plants. You shouldn’t put a rose just anywhere; roses want a lot of sun (at least six hours a day) and soil that drains well and is moist. An azalea would love all of that moisture but would fry in so much sun. A brief time out for a personal plea: Can we please stop planting the European white birch on the Peninsula? Yes, it is a gorgeous tree, with its peeling bark and graceful, tumbling branches. But it likes to be in moist soil — which few of us have — and it is terribly susceptible to aphids, who provide a steady drip of "honeydew.” (If you don’t know what honeydew is and are feeling reckless, park your car next to a birch).

Your planning should also consider creating convivial communities in your garden: grouping plants that like the same conditions. Azaleas, rhododendrons, ferns, astilbes, begonias and Japanese maples are happy in moist shade. Don’t sentence them to a life of misery by planting them with salvias in your sunny border.

As pretty as moisture-loving plants are — and no one loves a rhodie in full girly flounce than I do — in most areas of San Mateo County, planting them makes it more difficult and expensive to keep your garden in good shape. You end up having to fuss over them — constantly checking for moisture — because they don’t naturally do well in our summer-dry Mediterranean climate (They long to be in Seattle and Tokyo, not in San Carlos).

Which leads me to sing the praises of California native plants. They are a hardy bunch that grew up in California, which means they thrive under our natural gardening conditions. A mature California oak, in silhouette against the evening sky; and the violet blue flowers of ceanothus, humming with bees probing for nectar, instantly lift your spirits and ask only for an occasional drink of water and a little pruning.

However, not all natives do well anywhere in California. For example, unless you live on the coast, don’t plant a coast redwood (sequoia sempervirens) in your garden (I’m talking to you, Redwood City). It wants moderate to regular water, and is happiest in light shade. Otherwise it pouts, grows slowly and gets lanky.

Finally, as you ponder how to fill in those holes in your garden, think about the mature size and shape of the plants you are considering.

One of the most common mistakes I see as I walk through neighborhoods is plants planted too closely together. Folks, the heart of a hydrangea is to be big: the common garden hydrangea (h. macrophylla) wants to be from four- to eight-feet tall and just as wide — maybe more. If you don’t give her the room she wants to grow, you will have to constantly prune her.

In addition to size, plant to accommodate a plant’s natural shape. If its nature is to be a mound with a three-foot diameter, plant it so that it is centered in a space that will allow it to do its thing. So often I see shrubs jammed up against a brick edging and then pruned to a boxy shape to keep them from extending over the edging. Instead, judge how wide your plant will be at maturity, and figure where to plant it so it is centered. Yes, it won’t look as lush at first, but you will save yourself time and spare yourself grief by putting it in its proper spot.