The Dry Garden: Spacing plants so they have room to bloom
The single hardest thing to remember in fall planting season is restraint. After summer dormancy, everything looks so fresh. Salvias are pushing out their autumn blooms. We gardeners are full of pent-up expectation. Everything feels possible! Many things are. Keep that elation. Just resist the urge to crowd young plants during installation, a temptation so strong that almost everyone does it.
The problem may be that we treat young plants like babies, which in some ways they are. Like us, they start small and then grow. But we replace cribs with twin beds and twin beds with double beds and may even redo the basement so a 6-foot-tall baby can have a queen. With plants, you have to start out envisioning a queen-sized bed for the newborn or, in the case of many shrubs and woody perennials, you can easily end up with the horticultural equivalent of John Goodman in a crib.
Do not look to most newly installed civic gardens for a good example. Landscape architects are among the worst offenders when it comes to crowding. Most pack new installations with young plants to create an instant sense of fullness, leaving a client briefly pleased but facilities staff invariably resentful as they must dig their way out of a mess.
Others argue that you can mitigate overcrowding by buying larger specimens. Start big! After paying your chiropractor for the damage to your back trying to place 15-gallon toyons along a hedge line, never mind getting them level and moving astonishing amounts of dug-up soil, you might regret the decision.
Moreover, if you buy woody perennials or shrubs in anything larger than a one-gallon pot, the price jumps precipitously while the remaining lifespan of the plant drops proportionately. That's particularly true for our most beloved lavender and ceanothus, which might only last a decade anyway.
Another justification for crowding is that you can prune your way out of it. In other words, all you have to do to John Goodman as he grows is cut off his arms and head. But reducing a plant to its ankles carries a toll on its health. You’re not only sacrificing the beauty of the natural form, but also signing up for an expensive maintenance treadmill.
Restraint wouldn’t be so rare if it weren’t hard. Over-buying is almost irresistible when you’re holding a six-pack of coral bells, or a pint-sized pot of an ornamental grass, or a one-gallon agave or lavender or sage or ceanothus or (fill in the blank). It’s almost impossible to believe that the itsy-bitsy, got-to-have-10-of-them Cleveland sages each might reach 4 to 6 feet in diameter in three years. But they will.
So go to the nursery with measurements of the space you want to fill. Read the plant tags. Then if you have intimidating blank space left over after planting, brandish that secret temporary space filler: wildflower seeds. California poppies are perfect -- low-growing, fleeting and easily thinned. In lieu of a long-term woody mess, you have the ephemeral washes of color prescribed by nature itself.
-- Emily Green
"The Dry Garden," Green's column on sustainable landscaping, appears here every Friday. For an easy way to follow future installments, join our Facebook gardening page.
Top photo credit: Los Angeles Times