Tasks in the Winter Garden
By Aileen Carroll for Van Winden’s Garden Center
Working outside in the winter garden reflects the season - it’s a slow time, perfect for those projects that get put off during the busy spring and summer. Plants are growing slowly right now, or they’re completely dormant so there is (hopefully) no urgent need to water, fertilize, or deadhead. Winter is also when you should take advantage of the short bare root season for roses, fruit trees, strawberries and more.
Winter is the only time of year when bare root plants are available. Sold leafless and when their roots are exposed, (hence the name) bare root roses, fruit trees, strawberries, asparagus, and horseradish are available for short windows of time in January and February. Experienced gardeners know to take advantage of this hyper seasonal offering because long term plant health and vigor is strongly correlated with the root health at the time of planting. This is when reputable garden centers have their largest selection and lowest prices of the year for roses and deciduous fruit trees.
Winter blooming flowers like afternoon-shade-loving and drought-tolerant camellias are ideally sourced now, when their flowers are visible. Winter annuals like cyclamen, pansies, violas and primroses will keep putting out new flowers until the weather warms up around May. Tuck them into pots or in the front of your garden beds for a pretty pop of color.
The dormant season is ideal for structural pruning of woody plants, both to maintain aesthetics and to improve health. Dead or dying limbs should be cleanly removed with a sharp pair of pruners or a saw. Branches with poor attachments to the trunk, or those that have grown to cross each other, should be reduced or removed.
Prune roses back to knee height by removing small branchlets less than a pencil’s thickness, taking care to leave at least two thirds of the plant and a foundation of strong canes for next year’s growth. Here in the Napa Valley it is also usually necessary to manually remove all the leaves from your rose so you can have a fresh start with disease threats in the spring.
Assess deciduous fruit trees and berry plants for pruning needs as well. Reduce branches to keep fruit trees smaller and stronger. Small trees are easier to harvest from, and
it’s best to establish a small framework in the first few years that the tree is in the ground.
Apply fungicides, such as copper, to plants that are susceptible to fungal diseases in order to reduce the number of overwintering spores. For example, treatment of peach leaf curl for peach and nectarine trees involves multiple applications of copper spray in December, January and February. Apply a horticultural oil spray to help eliminate overwintering aphids and mite pests that shelter themselves in the crevices of plants. If your plum had curly leaves last summer an application of oil now is important! Good fruit tree hygiene includes removing any rotten or mummified fruits and keeping the area underneath your fruit tree free of debris.
Weeding is also very important in these early months. Catching weeds when they are very small in January will save you a headache in May! On hard packed surfaces, a tool such as a hula hoe is ideal. Areas with loose soil or mulch should be hand weeded or potentially sprayed with a capric acid-based herbicide.
Winter is also an excellent time to assess your planting layout. Relocating plants is best done in the dormant season as the physical trauma to the roots will not be compounded by the higher water demand of spring or summer. When digging up woody plants, excavate as much of the root ball as possible. Use the drip line of the plant, which is the extent of the canopy, as a guide for how wide your root ball should ideally be. Perennials or bulbs, in contrast, do not require as extensive root systems for replanting. Transplanting is best done when the ground is moist but not soggy, and it is important to keep transplants well-watered as they get reestablishedz
Dormant and well-established plants in the ground need very little supplemental water in the winter. Turn off or reduce any automatic water systems. Potted plants will need a little more attention. If your potted plants receive rain, check to make sure that the soil is draining properly with no standing water in the pot. For plants that are tucked under the eaves of buildings, water as needed.
Perhaps the gentlest of winter tasks for the home gardener is planning for the coming year. Our cold and rainy days are perfect for sitting down with garden sketches and inspirational photos from Pinterest. As the days get longer be sure to notice where and when sunlight touches specific parts of your garden. This information is incredibly valuable when you shop for plants. Making planting plans for spring flowers and summer vegetables will help speed the dark days of winter along!