January is the month of rain, snow, ice, freezing temperatures, fog and wind. Sounds good? Growth slows down in winter, but it does continue. Even plants that are dormant are still growing, often only underground, and they are preparing for spring. Some plants, like many bulbs and wildflowers (and annuals we consider weeds), are actively growing now. Winter and early-spring blooming shrubs, bulbs and perennials love frosty, damp, or foggy weather. Moisture that is not used is stored deep in the soil for summer use.
Planting: It’s possible to plant in winter, but we can delay most of our planting until the (relatively) warmer days of mid to late February. The exception is bare root planting. Here are some tips:
Bare root fruit trees are now available. Check their pollination requirements. Not all fruit trees are self-fertile, and some will require a cross pollinator. Notice the number of chill hours required. Our winters average 700-800 chilling hours.
Bare root roses—Hybrid teas, floribundas, climbers, miniatures, ground covers and shrubs are available. All roses do very well in the San Joaquin valley.
Bare root berries and grapes—Plant grape vines, cane boysenberries, blackberries, raspberries, blueberries, and strawberries.
You can also plant beets, carrots, leek, lettuce, onion, parsley, radish, seed potatoes, onions, peas, radish, spinach, artichokes, and asparagus directly in the garden this month. Believe it or not, it’s time to begin sowing seeds for summer annual flowers and vegetables like tomatoes and peppers. Place your planted trays in a protected location where you can keep the seedlings warm and where they will receive enough light. Sow more wildflower seeds, especially in gravel or rock where they will receive a little warmth.
Maintaining: We have less to do in January, but there are a couple of chores that are perfect to do this month. One of them is spraying roses, deciduous flowering trees and deciduous fruit trees with winter horticultural oil to smother overwintering insects like spider mites, scales, mealy bugs, and peach twig borers. You don’t have to apply horticultural oil if you are lucky enough not to have these specific pests, but if you’ve had a problem every spring, summer, or fall, be proactive now and keep your trees and roses healthier year-round. Spray the branches, crotches, trunk, and the ground beneath the tree’s drip line. Hold off spraying if rain is forecast, or if the temperature is below 45 degrees. Never spray oil on walnut trees. If you didn’t spray your peach or nectarine tree for peach leaf curl in November or December, spray now with a copper-based or a synthetic fungicide.
The other main chore of January is pruning deciduous trees and deciduous shrubs, including roses. It was hard to find a stretch of dry, low-humidity days in December to get an early start on pruning. The perfect weather is a stretch of those crisp, sunny, low (relatively) humidity days and nights. At the very least, hold off pruning if rain or frost is expected within the week following cuts. For all pruning chores, keep pruners & loppers sharp. Sterilize the pruners between plants.
Use a 10% bleach solution or white vinegar and rinse or wipe blades off with a clean cloth or paper towel after sterilizing to remove the chemicals. You won’t see the effects of fungi and bacteria you’ve contaminated your plant with until spring and then we want to blame what we see, which is often insects, instead of our own past practices.
Remove all broken, diseased, or crossing branches first. Two basic cutting techniques are used in general pruning: thinning and heading. Thinning cuts remove entire branches back to a larger branch or the trunk, resulting in a more natural look. Thinning cuts are also used to allow more air circulation and light into the interior of the tree. Thinning cuts are made first, before heading cuts. You might want to take a break midway through and step back to examine the tree from a short distance. A well pruned plant looks balanced and strong.
Heading cuts shorten branches and should only be used on small branches. Use heading cuts judiciously to shorten over-long branches. You can take off about a quarter of the previous season’s growth on these newer smaller branches if you want to keep the tree smaller. Make sure to cut back to an outward facing bud to direct new growth away from the interior of the tree. Prune from the bottom up and from the inside of the plant to the outside. Don’t be too nervous about it. Healthy trees will recover and regrow if you make a mistake.
Keep up with weed control. Add more mulch to depleted areas so there is always a three-inch layer of organic mulch or a two-inch layer of rock or gravel mulch.
Monitor or turn off your irrigation controller if you haven’t already. Deep water if we have an extended dry period, but don’t waste water and energy on water if we don’t need it. Remove the mulch in a few areas to check soil moisture. It may be cool and foggy enough to not need to water even if we have two or more weeks between rainstorms. Over watering is stressful to plants, especially in anything except sandy soils.
Conserving: Instead of sending leaves from healthy trees off your property, shred them and use them as mulch or in the compost bin as much as you can. Nature does not like bare soil, and good gardeners understand the importance of caring for the soil by covering it and protecting it from wind, rain and extreme temperature assaults, and by feeding it with organic material that can decompose and support soil organisms.
Let’s start planning our garden year and consider making a few more changes towards a more balanced, less chemically dependent garden. Bundle up and spend some time in the garden without working in it. Is it a place that connects you with nature? That gives you calm and pleasure? If not, what changes can we make in 2026? Happy New Year!
This column is not a news article but the gardening advice and opinion of the writer, and does not reflect the views of Mid Valley Times newspaper.
Comments are closed.