Monthly Garden Tips

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January Monthly Gardening Tips

• Continue to monitor weather forecasts for nighttime lows. To protect frost-tender plants such as Citrus, Bougainvillea, Hibiscus, and Tibouchina, use an anti-desiccant spray such as Cloud Cover or a spun fabric floating row cover when frost is actually predicted. Covering plants with sheets or lightweight blankets or burlap is another option. If you use plastic sheeting, do not allow plastic to contact foliage. A strand of Christmas lights in a tree is often enough to protect a plant.
• This also might be a good time to replace any plant that can’t tolerate the cold with one more appropriate to your microclimate.
• Clear vegetation debris when the ground is dry enough to walk on. It is important not to clear brush and trees during bird nesting season March 1st to August 31st to protect our bird populations. 
• Bareroot shrubs and trees will begin appearing in nurseries. Bareroot is a good way to plant many fruit trees, shrubs, and roses. If you can’t plant the day of your purchase, submerge roots in a bucket of water up to 24 hours and plant as soon as you can.
• Roses should be pruned between New Year’s and Valentine’s Day. Be careful not to compact soil around plants with your feet when you prune. Prune hard, leaving 3-4 young, vigorous canes per plant.
• Don’t forget to take care of tool blades. Winter gardening break is a perfect opportunity to have blades sharpened for cleaner cuts of lawn, shrubs, and trees.
• Clean, oil, and store tools such as shovels, hoes, and pruners. Use light machine oil on metal parts to prevent rust.
• While you are cleaning, consider spray painting tool handles a bright color. It’s a helpful way to keep your tools separate from any you borrow or lend out, and it makes them easier to find in the yard.
• Prune pines and other dormant conifers, but do not trim back individual branches part way. Rather, thin where necessary by pruning out entire branches to the base. You can control the size of most pines by pinching out new shoots, called candles, at the tip of each new growth cluster. Always avoid topping trees which causes irregular growth.
• Begin to cut back deciduous ornamental grasses, pruning within a couple of inches from the ground. Wait until February or March if you like the existing structure. Winds often blow dried stems away from unpruned grasses.
• Winter is the season when rats forage—and damage—ornamental plants. If you have had problems in the past or if your neighbors have noticed rats, put out traps early before they damage fruit trees, vines, climbing roses and shrubs.
• Rats favor heavy cover like overgrown ivy. If you have ivy, the best time to prune or remove it is winter when growth slows and soil is somewhat soft. If you wait until spring, ivy will quickly grow back, and roots will be harder to remove.
• January is a good month to think about garden design and plan for early spring plantings. Use this time to review favorite garden books and catalogs, make notes and designs, and compose plant lists. Refer to the Vegetable Planting Summary for vegetables and herbs, to https://sonomamg.ucanr.edu/Recommended_Plants_for_Sonoma_County/ for ornamentals.

February Monthly Gardening Tips

• Continue to monitor weather forecasts for nighttime lows. To protect frost-tender plants such as Citrus, Bougainvillea, Hibiscus, and Tibouchina, use an anti-desiccant spray such as Cloud Cover or a spun fabric floating row cover when frost is actually predicted. Covering plants with sheets or lightweight blankets or burlap is another option. If you use plastic sheeting, do not allow plastic to contact foliage. A strand of Christmas lights in a tree is often enough to protect a plant.
• With a water deficit from recent drought years and scientists’ warnings about ongoing drought, conservation efforts remain important. In preparing for spring planting, plan to plant only the food crops you will consume and ornamentals that require limited irrigation. Install drip systems in all garden beds, add water-holding compost to the soil, and plan to mulch.
• Clear vegetation as soon as possible. It is important not to clear brush and trees during bird nesting season March 1st to August 31st to protect our bird populations. 
• Finish pruning roses. A general practice in Sonoma County is to have them pruned by Valentine’s Day.
• Also finish pruning summer-flowering and foliage trees as necessary. Deciduous trees are much easier to prune when leafless, as the branch structure is more clearly visible. Cut out all crossed and damaged branches and prune for shape.
• Ornamental grasses that are not evergreen should be cut back within a couple inches from the ground to make way for new shoots. To make cleanup easier, tie twine or a rope around the grass clump before cutting, and then simply pick up the bundle and put it in the compost or shredder pile. Winds often blow dried stems away from unpruned grasses.
• Don't cut back evergreen grasses such as Carex or Helictotrichon. Use your hand or a small rake and tease out dead blades. Deer grass (Muhlenbergia rigens) may be left unpruned for 2 or more years before cutting back to renew clumps.
• You can plant bare root trees and shrubs that are now available at nurseries.
• Snails may begin making their presence known, either directly or by holes they eat in leaves. Removing by hand is an effective control method, but it takes dedication to go out in very early morning or after dark armed with a flashlight to catch as many as possible. The more you control snails before they lay eggs, the fewer there will be later.
• Clean and sharpen garden tools using a rasp or stone. Sharp pruners are easier on both plants and your joints. Storing hand tools year round in a 5-gallon bucket of sand with some vegetable oil mixed in helps keep them sharp. Every time you push them into the sand, the tools will get an effortless cleaning and lubricating. Motor oil isn’t recommended, as it’s harsh on hands and difficult to dispose of properly.
• February is a good time for washing out old pots and trays. You can put clay pots in the dishwasher after first rinsing off dirt and debris. The dishwasher will sterilize them and they’ll be ready for spring planting. Rub pots with linseed oil after cleaning to make them more attractive.
• Next year’s gardening will be easier if you remove Poa annua, the weedy annual bluegrass, before it goes to seed.
• As you plan spring plantings, remember that color not only creates mood in the garden, but it also defines space and proportion. Select cool tones such as blues, pinks, and purples for a sense of serenity. Warm tones like reds, oranges, and yellows create a sense of good cheer. Blue gives the impression that the garden is distant while red makes a flowering or foliage plant look closer than it really is.

March Monthly Gardening Tips

• Carefully monitor soil moisture and apply supplemental water to plants as necessary.
• Fertilize roses. Give them a first application at bud break then once a month thereafter.
• Fertilize other perennials that are emerging from winter dormancy. 
• If you still have a lawn, apply a half-dose of fertilizer now and again in 6 weeks. If the thatch layer is more than ¾ in. deep, de-thatch. Dethatching relieves compaction and improves aeration and water absorption. It is possible to have a beautiful, healthy lawn with minimal reliance on chemical fertilizers and insecticides and lower water use. Better yet, take the plunge and decrease the size or remove it altogether, and replace water-demanding grass with a water-wise garden.
• Plant summer bulbs such as gladiolus, dahlia, callas, amaryllis, and lilies.
• Continue to look for and control snails. Hand pick them or apply Sluggo (non-toxic to pets, children, and wildlife) to control snails that are hatching now.
• If you have not yet pruned summer-flowering shrubs, such as crape myrtles or any that bloom on new wood, do it this month.
• Watch carefully for aphids on tender new growth and use insecticidal soap or spray with water from a garden hose as necessary. Sonoma County is usually not warm enough in March for them to be much of a problem, but be alert if we have an early heat wave.
• Excess nitrogen fertilizer stimulates new growth that is attractive to aphids.
• Pull out what weeds you can by hand. If you get to them before they go to seed, put them on your compost pile. However, to avoid compacting the soil, avoid walking on planted areas sodden from rains.
• Use a few layers of newspaper or cardboard and cover with mulch to discourage areas of unwanted grass or weeds. By the end of the season, the paper barrier along with dead grass and weeds will be decomposed and become compost.  
• Very hardy flowers can be planted 4-6 weeks before the average frost-free date; in Sonoma County, that is April 15. Indoors, sow warm-season flowers such as ageratum, celosia, cosmos, marigolds, sunflowers, and zinnias.
• If you’ve started plants in peat pots indoors, in a cold frame, or greenhouse, make sure that when you transplant them into the garden, you either bury the entire pot completely or cut off the part that will be above ground. That excess portion will suck moisture out if exposed to open air.
• To speed up decomposition in your compost pile, add sources of nitrogen such as food scraps, alfalfa meal, blood meal, cottonseed meal, or fish meal and stir the pile every day or two.
• Remember, the last frost date in Sonoma County is April 15th. Don’t be fooled by any heat spells; cold nights are still possible.

April Monthly Gardening Tips

Rains generally taper off in April, so be prepared to start your irrigation system. Late rains or lack of rains affect the need for supplemental water. Stay focused on climate-appropriate plants that can withstand dry summers.

• As rain tapers off, check your irrigation system for cracks, leaks and clogs. Dirty filters can wreak havoc, especially if you are on a well. Clean out filters and replace as needed.
• Flush out drip systems and make sure all emitters are working. Replace batteries on systems that use battery-operated controllers. Ensure that timers are working. Do this now before it gets really hot and dry and plants need water immediately.
• Monitor soil moisture in planted areas so you know when to begin irrigating. Soil may dry out an inch or so on the surface but still retain ample moisture under mulch in the root zone around well-established plants. Hand water new plants as needed.
• Continue to lightly fertilize perennials that are emerging from winter dormancy.
• If growth has not yet begun, there is still have time to prune summer-flowering shrubs.
• Aphids will flourish on tender new growth in warm weather; use insecticidal soap or spray with water from the garden hose as necessary. Wash off spittle bugs.
• The ground is soft enough to make weed pulling easy—stay ahead of it and you will have fewer weeds going to seed.
• Fertilize or amend soil around azaleas and rhododendrons with acidic material or acid fertilizer. Work carefully to avoid damaging shallow roots; add mulch.
• Sow hardy annuals in pots or directly in the garden.
• Plant summer bulbs and rhizomes.
• If you still have a lawn, apply another half-dose of organic fertilizer now. It is possible to have a beautiful, healthy lawn and lower your water use without reliance on chemical fertilizers and insecticides. Most inorganic products contain a form of nitrogen that easily washes away and enters ground water and waterways.
• April is a busy time for finishing debris clean-up from late winter and early spring and for cutting back cold-sensitive, summer-blooming perennials, such as salvia, nepeta and penstemon. Leave fading foliage of spring bulbs and let them whither; they provide nutrients for next year's blooms.
• The last frost date in Sonoma County is April 15 although there still may be very cold nights ahead.

May Monthly Gardening Tips

• Spring rains are usually over by May and gardens may begin to need irrigation.
• If you didn’t trouble-shoot your irrigation system for cracks, leaks, and clogs last month, do it now. Dirty filters can wreak havoc, especially if you are on a well. Clean out filters and replace as needed.
• Flush out drip systems and make sure all emitters are working. Replace batteries on systems that use battery-operated controllers. Ensure that timers with batteries are working.
• If you start to irrigate this month, practice water-conservation by watering in early morning or evening and using slow release methods such as drip or soaker hoses.
• It’s time to plant flowering annuals and all summer veggies—beans, cucumbers, eggplant, kale, lettuce, melons, peppers, squash, and tomatoes. If you don’t have a dedicated vegetable garden, consider planting a few veggies in the ornamental garden. Leafy greens in particular make attractive additions to beds and borders.
• Be sure to acclimate transplants started indoors before planting them in garden beds. Harden off transplants by setting pots outdoors during the day and moving them indoors at night for a few days before leaving them outdoors for several more days. Tender seedlings may succumb to drastic changes.
• When planting and transplanting, watch sun exposure and heat. When transplanting young plants into direct sun, provide some shade. Setting up lightweight lawn furniture is an easy solution for creating shade until plants become accustomed to their new location. Wait until fall and the onset of the rainy season for any major planting and transplanting projects. New plants struggle and often fail in summer heat.
• Add edible flowers to your garden for a pop of color and to attract beneficial insects that pollinate food crops and ornamentals and provide an ecological balance against harmful pests. Common edible flowers include carnations, violas, lilacs, roses, lavender, marigolds and nasturtiums as well as flowers of rosemary, basil, thyme and sage.
• Continue to fertilize roses and other heavy feeders.
• Check for weeds to emerge where garden areas are irrigated.
• Prune all spring-flowering trees and shrubs after bloom. Pruning forces new growth that will bear flowers next spring.
• May is a windy month in much of Sonoma County. Take care that new plantings, especially trees, are staked properly.
• Deadhead azaleas, camellias, and rhododendrons once they’ve finished blooming. An estimated 70% of a rhododendron’s energy goes into the formation of seed. Use a whisk broom to lightly dislodge spent blossoms on azaleas. Use pruners or 2 fingers to deadhead flowers on rhododendrons and cut just above the 2 new leaflets. During spring and summer, feed these shrubs monthly with a balanced organic fertilizer formulated for acid-loving plants.

June Monthly Gardening Tips

Mulch in the garden not only adds a decorative element but also a practical one. A 3-4 in. thick layer of mulch keeps weeds to a minimum going forward.

• Be sure to mulch around new plantings to cut down on weeds and prevent soil from drying out quickly. Keep mulch at least 6 in. away from the base of all woody plants—trees and shrubs—to prevent fungal growth that can cause fatal damage.
• Continue to fertilize roses and other heavy feeders. Gardeners who have regularly amended their soil with ample compost and mulch at least once a year have found that additional products are seldom needed.
• Dead-head roses frequently. Cut stems for bouquets early in the morning and quickly sink them into deep, warm water. They will remain fresh longer in vases.
• Pull or cut suckers from the base of sucker-prone plants such as wisteria, crab-apples, poplars, and fruit trees.
• If you have wisteria, prune it aggressively after bloom, cutting back to 2 nodes on new branches to ensure a robust display of blossoms next year. Prune again in the fall.
• As the weather warms, any aphid problem will lessen but stay alert for remaining or new colonies; spray them off with water.
• Fill in empty spaces in flowerbeds or borders with annuals such as zinnias or impatiens.
• If you plan to be away this summer, ensure that you have someone available to water plants. If not, set up your irrigation system on automatic timers.
• In the midst of June chores, enjoying the garden is high on an activities list. Plentiful flowers bring out bees and hummingbirds in full force, and many other birds are still busy courting and building nests.

July Monthly Gardening Tips

July is the month in Sonoma County when gardeners typically start to observe water problems, especially if they have not been practicing waterwise gardening methods. Learn about waterwise gardening and irrigation techniques elsewhere on our website.

• We are now well into the hot, dry season; check to make sure all irrigation systems are working and drip lines have not been disturbed by pets or wildlife.
• If you planted any trees, shrubs, or perennials this spring or summer, they likely need extra irrigation to adjust. Foliage and root growth may be stressed. Root balls must never dry out while plants are getting established. Water them evenly and thoroughly to encourage both lateral and deep root growth. Test root balls frequently for moisture.
• Avoid killing spiders in your garden. Spiders do not harm plants and they help keep down other insect populations.
• Weeds are usually more vigorous than flowers and will rob plants of water and nutrients. Remove weeds regularly especially before they produce seed.
• Cut back flowering perennials such as nepeta, diascia, and penstemon to force new growth and keep their blooms coming. 
• Deadhead perennials and annuals such as heuchera and petunias to prevent them from setting seed, which slows continued flowering.
• If you are looking for summer color, continue to add annuals to beds and containers. However, no matter how tempting it is, try not to do any major planting of perennials, shrubs, or trees in summer.
• If you find plants at the nursery that you cannot resist, make sure that if you plant them in established beds, you are vigilant about keeping them frequently watered. Another solution is to designate an out of the way, shaded spot and group together any summer purchases. Check them every other day or so and water as needed. Small pots may need watering once a day during heat waves. Plant them in the fall once rains resume.
• Garden work lessens in July, a good time to observe and plan. Many gardeners take a notebook and pen and look around the garden, making a list of plants pleasing for their color and location and those that are not. Note particularly successful combinations that deserve to be repeated elsewhere in the garden when new planting begins in fall.

August Monthly Gardening Tips

With continued irrigation, the ornamental garden largely takes care of itself this month as summer winds down, though there's always activity in vegetable beds. This is a month of planning for fall and keeping your eyes open for plants under stress.

• If you’ve never planted a fall or winter vegetable garden, think about doing it this year. See our Food Gardening section for some inspiration and details.
• Stay alert to signs of water stress, especially for plants in containers and hanging baskets. An occasional deep soaking during periods of high heat benefits most plants, even those that do not require regular water. Make sure your garden is well-mulched to conserve moisture.
• If you have a lawn and want to conserve water or reduce your water bill, you can forgo watering without inflicting permanent damage even though grass may turn brown and lie dormant. To reduce stress, keep grass 3 in. high and do not mow too often. Don’t fertilize either, as this simply stimulates new growth that requires more water. Better yet, remove turf altogether and rely on low water-use plants.
• Continue to deadhead perennials and annuals, especially those in containers. Summer heat takes a toll on some annuals and showy perennials. Periodic freshening will keep containers going through the fall. Heavy bloomers can be trimmed and fertilized.
• With major summer chores behind you, continue to check staking on trees, supports for vines, and other general structural needs.
• If you plan to be away this summer, ensure that you have someone to water or set up your irrigation system on automatic timers. When you return from vacation, do a check of the entire garden to make sure that nothing was ignored while you were away.
• Start making a checklist of fall chores that may be unique to your garden. Plants that need to be moved or divided, for example, will appreciate your waiting until shorter days and cooler, moister weather. If you want to reduce water usage in the future, make a list of the biggest water-hogs in your garden and decide if they are worth keeping or can be replaced in the coming months with more drought-tolerant species.
• Despite daytime heat spells, balmy evenings in most of the county prompt many gardeners to sit out in the warm twilight, often setting up a table for dining outdoors when the garden feels fresh and inviting.

September Monthly Gardening Tips

Growth is slowing for most perennials since they monitor day-length, not temperature, but your garden may still need extra water during particularly hot spells. September is generally a very dry month, and it is not unusual to have some periods of heat before cooler weather sets in.

• Before fall planting and winter-readying begins in earnest, take advantage of plant sales at local nurseries. Several specialty nurseries have fall sales lasting a few weeks or longer. Websites are a good way to get information quickly; shopping early yields best selections. Caution: many sale plants are pot-bound and need extra care when planting. Some can be divided, doubling your savings. Any that are not planted right away need to be kept well-watered.
• Look for plants that have good fall color. Fall display is often neglected when planning gardens. Some species that enliven the landscape with September and October color are Sedum ‘Autumn Joy’, Ceratostigma, Viburnum, Cotoneaster, Cornus stolonifera, Cotinus, Berberis, crab apples, and Persimmon as well as smoke tree (Cotinus coggygria), red maple (Acer rubrum), and Chinese pistache (Pistacia chinensis). For crape myrtle blossom color, make selections before flowers die back. Many ornamental grasses continue to look their best through fall.
• September is a good time to tour local gardens such as Sonoma Botanical Garden or Luther Burbank Gardens to observe their foliage displays.
• Fall is also the right time for planting California natives. Native plant sales offer numerous species, such as Arctostaphylos, Ceanothus, and Rhamnus for structure; Ribes sanguineum, native Salvia, Epilobium, Penstemon, and Eriogonum for color and to attract pollinators and other beneficial insects.
• Spring-flowering bulbs begin appearing in nurseries and garden centers. It is generally easier to wait until after the first rains to plant them, but make purchases ahead of time so you are prepared.
• Continue to build your checklist of fall chores, including plants that need to be moved or divided during shorter days and cooler, moister weather. With a few exceptions, fall-blooming plants should be divided in spring, spring-bloomers just after flowering, and summer-bloomers in fall. Share your divisions with garden friends.
• September is a wonderful time to be in Sonoma County gardens. Popular activities are a harvest meal under a trellis or an afternoon barbecue, especially where colorful foliage or ornamental grasses are back-lit by the sun.

October Monthly Gardening Tips

• Once rains begin and the ground is moist, it’s ideal planting time in Sonoma County. While the soil is warm, roots on new plants begin to take hold and boost growth even as days cool down. Take a look around the garden to see if existing perennials could be divided and transplanted now, too.
• It’s time to begin fall chores. If you have deciduous trees, stay ahead of their fallen leaves. Shred or run a lawn mower over large leaves before composting. If large, moist leaves are not shredded, they will mat together while still moist and decompose slowly, making a slippery, gooey mass in your compost pile or on beds.
• If you still have a lawn, don’t cut it too short for the winter—about 2 in. is best. Put down a half dose of organic fertilizer now and again in 6 weeks. In early spring, follow the same regimen. This schedule will keep your lawn healthy but not produce tremendous bursts of growth that require frequent mowings. To fill in bare patches, sow seed and water lightly for germination before heavy winter rains wash seeds away.
• If you have particularly weed-prone areas or troublesome varieties such as annual bluegrass (Poa annua), this is a good time to use pre-emergent weed killers on this and other annual weeds prior to germination
• If you haven’t been cleaning up leaves as they fall from roses, be sure to do it now. A single rose leaf on the ground can carry millions of tiny fungal spores that overwinter and infect roses the following year. Put leaves in the trash, not the compost pile.
• Fall sales are still on at many local nurseries. Look for bargains but be mindful that many sale plants are root bound and will need to be watered regularly before winter rains begin. Trim any rootbound plants up to an inch around the sides and bottom of the root ball and loosen the remainder. Do not buy anything you can’t put into the ground and keep watered. Some pot-bound perennials can be divided 2-3 times before planting; use a pruning saw or large serrated kitchen knife to cut through the root ball.
• Bulbs are on display in nurseries and garden centers and good selections are available from specialty catalogs. It is generally easier to wait until after the first rains to plant them, but buy now so you are prepared.
• As days become cooler and shorter, you can begin to divide and transplant ornamental grasses and clump-forming perennials. Keep the divisions well-watered until it rains. It’s easier to divide grasses if they are first pruned low to the ground.
• If, in the coming weeks, this turns out to be a dry fall, make sure you continue to irrigate and not wait each day for rain to come. Pay special attention to new plantings and those in containers.
• If you have soil high in clay content or sand, apply ample amounts of compost this fall. Spread it out about 3-4 in. deep and work it lightly into the top few inches of garden beds, avoiding digging deeply. Compost will slowly breakdown and improve soil structure over time, allowing for improved drainage as well as water retention and increased nutrient uptake. Apply additional compost and mulch again in spring.
• Perennials should be completely dormant before you cut them back to just above ground level from November to January. It’s too early to start now, but not too early to take note and make lists. Leaving foliage intact allows leaves to continue feeding the root system throughout fall. You can cut back flowering stems and trim some unsightly leaves, but leave well enough alone until foliage dries completely or is killed by frost. Dead or dying leaves and often seeds provide habitat and food for wildlife throughout fall and winter.
• October is a good time to take hardwood cuttings of woody plants such as lavender, rosemary, and manzanita. Take small cuttings, dip them in rooting hormone, stick in damp vermiculite, and keep misted. Covering with plastic helps hold in moisture. Keep out of direct sunlight and wait for roots to form in several weeks to a couple of months, depending on the species.

November Monthly Gardening Tips

With a focus on dividing existing plants and putting new ones in the ground, try to conclude major chores before rains completely saturate soil and prevent working in beds.

• November is the recommended time to plant California natives. Hardy species suited to our climate and ecosystem need little water once established but require good irrigation to stimulate root growth; the best irrigation is our winter rainfall. Transplants often take 1-2 years to become established.
• Now is also the time to dig up and divide ornamental grasses and perennials. Their dormancy, shorter days, moist earth, and cooler weather all make this the least stressful time to disturb perennials. Make sure to keep roots moist once you’ve excavated a plant. Set plants in a shaded area and cover roots with damp newspaper while you are working.
• Keep in mind that the main success of any garden is healthy, productive soil, improved with an annual addition of 2-4 in. of compost or well composted, aged manure, or other organic material. Because fresh manure can quickly burn and kill entire plants, it’s important that it ages for several months before it has contact with foliage and roots. Work it into the soil a little or spread on top for mulch.
•  If you don’t have access to manures, then add composted organic material. Adding 2-4 in. of either is best. Your soil will be much improved by spring.
• If you have deciduous trees, rake up leaves as they fall. Shred large leaves before composting or run a lawn mower over them. If not shredded, large, moist leaves will mat and decompose very slowly, making a slippery, gooey mass in your compost pile or on beds. You can put them out for recycling as well, but it’s best to put their nutrients back into your own garden.
• Heavy feeders such as roses and fruit trees should get a good dose of organic fertilizer. Winter rain allows nutrients to penetrate into the ground where they break down and are ready to feed plants in spring.
• Turn off your drip irrigation systems if you haven’t already. However, if a few weeks go by with no rain, you will need to hand-water or turn your systems back on.
• Although days are often mild in November, we could have frost at any time. The first frost often occurs in the county in mid-November. Protect tender plants such as Bougainvillea, Hibiscus, Citrus, Tibouchina, and other tender species. You can use an anti-desiccant spray such as Cloud Cover or a spun fabric row cover. Covering plants with sheets or lightweight blankets or burlap is another option. If you use plastic sheeting, do not allow plastic to contact foliage. A strand of Christmas lights in a tree is often enough to protect a plant.
• Spring-flowering bulbs are on display in nurseries and garden centers and good selections are available from specialty catalogues. When the ground becomes soft from rain, put bulbs in the ground as soon as you can, following package directions.
• There are many ornamental plants that display dramatic leaf color in November: Chinese pistache, ‘Roger’s Red’ grape, Viburnum, Cornus (dogwood), Liquidamber, ash, crabapples, Cotinus (smoke bush), Nyssa sylvatica (tupelo), crape myrtle, and others. If you lack fall interest in your garden, consider adding one of these this month.
• There are also many annuals that provide winter bloom, such as Icelandic poppies, pansies or other Viola, Calendula, Cyclamen, and primroses. Most nurseries have a supply of six-packs of these and other winter bloomers.
• Hardwood cuttings can be taken at any time during dormancy, but just after leaves have fallen is an excellent time. Taking cuttings from leafless shoots is advantageous because water loss due to transpiration is minimal. You can bury the cuttings in moist sand or peat moss, put them in a cold frame or a sheltered area, and plant next spring. Ensure that they do not dry out.
• Clean up debris and fallen leaves from a lawn or the grass will tend to die out or discolor.

December Monthly Gardening Tips

Consider turning on your irrigation system if rains are delayed to be sure your garden is moist enough to prevent plants from drying out.

• Protect frost-tender species such as Bougainvillea, Hibiscus, Citrus, Tibouchina, and other tender species. You can use an anti-desiccant spray such as Cloud Cover or a spun fabric row cover. Covering plants with sheets or lightweight blankets or burlap is another option. If you use plastic sheeting, do not allow plastic to contact foliage. A strand of Christmas lights in a tree is often enough to protect a plant.
• You can still dig up and divide grasses and perennials if the ground is not completely saturated from rain. Moist earth, shorter days and cooler weather, combined with their dormancy, make this the least stressful time for disturbing perennials. Make sure that once you’ve excavated a plant to keep roots moist. Set plants in a shaded area and cover roots with damp newspaper while you are working.
• You can also continue to plant California natives and hardy trees and shrubs. Water well after planting in the absence of rain and do not allow root balls to dry out.
• If you have deciduous trees, rake up leaves as they fall. Shred large leaves before composting or run a lawn mower over them. If not shredded, large, moist leaves will mat and decompose very slowly, making a slippery, gooey mass in your compost pile or on beds. You can put them out for recycling as well, but it’s best to put their nutrients back into your own garden.
• Dormant-spray fruit trees and roses with horticultural oil after they have lost their leaves to control fungal infections and kill overwintering insect eggs.
• Whether using your own shredded leaves or purchased material, make sure your garden is amply mulched for the winter. Mulch will insulate roots and retard weed growth. Winter weeds grow prolifically in the rainy season.
• Plant any remaining spring-blooming bulbs. Sow wildflower seeds.
• Clean, oil and store tools such as shovels, hoes, and pruners. Use light machine oil on metal parts to prevent rust.
• Clean out gutters to avoid overflow and direct water to downspouts.
• Prune pines and other dormant conifers, but do not trim back individual branches part way. Rather, thin where necessary by pruning out entire branches to the base. You can control the size of most pines by pinching out new shoots, called candles, at the tip of each new growth cluster. Always avoid topping trees which causes irregular growth.
• Winter is the season when rats forage—and damage—ornamental plants. If you have had problems in the past or if your neighbors have noticed rats, put out traps early before rats damage fruit trees, vines, climbing roses and shrubs.
• Rats favor heavy cover like overgrown ivy. If you have ivy, the best time to prune or remove it is winter when growth slows and soil is somewhat soft. If you wait until spring, ivy quickly grows, and roots are more difficult to remove.
• Plant amaryllis or paperwhites indoors and decorate with evergreen boughs to echo the pleasing atmosphere of an outdoor garden.

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