McCreary: Gardening in wetter weather

As gardeners move back into the swing of things now that rains are on the horizon, questions arise by the bucketful. Here are a few I’ve encountered lately, along with brief answers and some general garden guidelines.

Q: How can I save rainwater?

A: To keep rainwater on site for your own use, install a designed or homemade collection system. Numerous techniques are illustrated online and sold locally in hardware stores.

To save rainwater in underground aquifers, it must be prevented from coursing to the ocean. We can only attempt that indirectly, by channeling runoff from slopes around our homes away from storm drains and into areas where it will be absorbed into the ground.

Covering all soil surfaces with plants, mulch or other permeable material lessens runoff and facilitates absorption into the soil. It’s also beneficial to replace solid landscape surfaces with permeable ones, and add gravel borders where that’s not feasible, such as alongside driveways and sidewalks.

Some gardeners handle runoff with a rain garden by excavating a slight depression or swale where water can collect around rocks or water-loving species. A berm or French drain will divert water to the holding basin.

Q: Should I cultivate my garden beds before their winter rest?

A: Rather than letting your beds rest, consider fortifying the soil and planting a winter garden. Late October is too late for starting nearly all cool-season crops from seed, but setting out transplants is still an option.

An important concern is that soggy soil should never be worked to prevent compaction. In fact, you may want to reconsider whether or not to cultivate garden beds at any time.

In his new book, “Understanding Roots” (Metamorphic Press 2015; www.robertkourik.com), Sonoma County horticulturist Robert Kourik provides excellent explanations and illustrations of the various components of the ecosystem beneath the soil surface and how disturbing that web of life can be detrimental to successful gardening.

Q: When should I plant a bareroot tree or shrub?

A: Bareroot plants are generally available in retail nurseries between mid-January and mid-March and should be planted as soon as possible after purchase.

You can plan ahead by preparing a planting hole now, before heavy rains make it impossible to work the soil.

If planting at purchase time is delayed, heel in bareroot plants - cover roots with damp soil or compost - until wet, heavy soil can be worked.

Q: What should I do when I find circled roots around trees and shrubs that I’ve purchased in a container?

A: Ideally, it’s best to lift a tree or shrub from the nursery can before purchase to check for circled roots and avoid those that are rootbound.

Once you have such a specimen, however, it’s been shown than trimming away the bottom layer of roots and untangling or shaving the entire outer rootball surface results in superior growth of both new roots and branches.

Kourik’s comprehensive treatment of root issues in “Understanding Roots” includes tips on dealing with these problem plants.

Q: Can I divide perennials now?

A: Yes. While soil still retains some warmth before winter cold sets in, plant roots have a chance to put on a growth spurt.

When winters remain mild, that growth continues uninterrupted, allowing many plants to become fairly well established by the time the ground begins to dry out in summer.

Q: Can I continue to make compost during cool and cold weather?

A: Composting accelerates during warm weather, when microorganisms are most active, breaking down organic materials and reproducing their populations.

As their numbers dwindle at low temperatures, so does the composting, but it does continue, albeit slowly.

To retain as much heat in the pile as possible, use a bin rather than an open pile and keep the pile as close as possible to 3 by 3 feet.

Piles of any size eventually break down.

Q: When is the best time to plant garlic?

A: If you follow the old saying, “Plant on shortest day, harvest on longest day,” you may find the ground too wet to work in late December.

Besides, garlic bulbs planted in October get started while the ground is still warm, have a longer growing period and will be larger than those planted later.

If you tend to delay gardening chores, you can still plant even after the first of the year, though bulbs will be small, for a June or July harvest.

Rosemary McCreary, a Sonoma County gardener, gardening teacher and author of “Tabletop Gardens,” writes the monthly Homegrown column for The Press Democrat. Contact her at rosemarymccreary@gmail.com or write to her at 427 Mendocino Ave., Santa Rosa 95401.