UC Master Gardeners, Santa Clara County, CA
University of California
UC Master Gardeners, Santa Clara County, CA

March Tips

Monthly tips are categorized by To-Dos, What to Plant, or Pests and Diseases. Scroll through the list to see items in each category. Also, refer to our list of tips useful for any month.

1. To-do

  • Navel Orange Harvesting -

    If you have Navel orange trees, the crop will be ripening. Oranges left on the tree too long will dry out and become inedible or get eaten by rats. Instead, harvest the entire crop by the end of April and use the bounty to make marmalade, chutney and spiced oranges.

    QUARANTINE WARNING: Most of Santa Clara County is under quarantine for citrus due to the asian citrus psyllid and huanglongbing disease. Check the Santa Clara County Quarantine Map to see if you're affected and review our asian citrus psyllid page for what can and can't be moved across quarantine boundaries.

    - February, March, April
  • Irrigation and Graywater -

    As temperatures rise, irrigation becomes more important. Container plants will begin to dry out and need to be checked every few days. Inspect irrigation systems for leaks, clogged drip emitters, misaligned sprinkler heads, and other problems which could waste water. Make sure the water is going to the root zones of the plants.

    Things to consider:

    Use a smart irrigation controller. These help adjust watering based on local conditions. Learn more about smart controllers.

    Collect water from the shower as it heats up and use it to water any plants.

    Use graywater from garage sinks and washing machines to water ornamentals and lawns. UC has a publication titled Use of Graywater in Urban Landscapes in California.

    - March, April, May, June, July, August
  • Pruning Dead Branches -

    As dormant trees and shrubs begin to leaf out, it will be fairly easy to see which parts are dead. Prune back to live wood to avoid diseases and keep your garden healthy. Swelling buds and a thin green layer just under the bark are signs that the wood is alive. Find tips on pruning at the UC Home Orchard website. If larger trees need pruning, hire a professional. The International Society of Arboriculture (ISA) has a searchable list of certified arborists.

    - March, April
  • Wet Soil -

    The clay soils which dominate our area are particularly susceptible to compaction, especially when they have received a lot of rain. These soils are characterized by small mineral particles. Hence squeezing out the air spaces makes it more difficult for plant roots and soil organisms to get the oxygen they need to flourish. Try to avoid walking on or using heavy equipment on soil that is wet. Digging in wet soil can also destroy the structure, breaking up useful soil aggregates and earthworm tunnels. Try to wait until the soil is moist, not wet or dry, for easiest tillage. If you must walk or stand on the soil, use a board to distribute your weight over a broader area. Mulch can also create a bit of a cushion and help minimize compaction.

    - February, March, December
  • Soil Management - Compost vs Mulch -

    Many home gardeners are confused about the terms “compost” and “mulch;” frequently these terms are used interchangeably, but they are not really the same thing. Here is a Comparison of Soil and Mulch from UCCE.

    Amend soil with compost to create soil that will retain water but still drain well enough for roots to have the air and water they need.

    Benefits of compost
    - Forms aggregate particles with clay
    - Creates larger pore spaces for water & air
    - Helps release nutrients from clay so that plant roots can absorb them
    - Supports the soil foodweb by providing nutrients for the organisms
    - Lowers pH somewhat.

    Benefits of mulch
    Mulch does not get worked into the soil. It sits on top of your irrigation system and helps:

    - Control weeds
    - Prevent erosion
    - Preserve soil moisture
    - Keep roots cool and moist

    - March, April, May, Any month
  • Bulb Care and Clean-up -

    Early blooming bulbs such as daffodils are already finishing flowering. Wait until the leaves have turned brown before removing them. The green leaves need to photosynthesize to store energy for next year's blooms. For more information see UCCE Tips on Flowering Bulb Care.

    - March
  • Growing Vegetables in Containers -

    Growing Vegetables in ContainersContainer grown vegetables can be decorative as well as good to eat. Almost any vegetable can be grown in a container if given the proper care. Eggplant, peppers, tomatoes, lettuce, onions, carrots, cucumbers and herbs do well. Use our Vegetable Planting Chart to decide when to plant.

    One of the biggest problems is that containers dry out very fast and nutrients wash away. Both are solvable. Do not use clay pots, which dry out quickly. Plastic, composite or wooden half-barrels are good, but avoid dark colors that can absorb heat. Vegetables like a roomy container.

    There must be drainage holes in the bottom but it is not recommended that you put pebbles or broken crockery in the bottom. Use a good commercial potting mix, not planter or planting mix. Group the containers together so they will shade one another.

    The hot summer sun can heat the soil to unhealthy levels. Water whenever the soil is dry. You can test by digging your fingers into the dirt. You may have to water more than once a day. A simple drip system is easy to install and will make your container garden almost foolproof. Fertilize every week with a water-soluble fertilizer.

    - February, March, April, October, November
  • Poison Oak -

    Poison oak is a California native plant that provides shelter and food for many native birds and other creatures. The downside is that at least 75% of us develop allergic contact dermatitis to the plant. Unwanted poison oak can be pulled or dug up by allergy-resistant friends, remove plants in early spring or late fall when the soil is moist and it is easier to dislodge rootstocks.

    A complete list of management options, including herbicide control, is contained in the UC Pest Note on Poison Oak. Under no circumstances should poison oak be burned.

    - February, March, April, November
  • Weed Management -
    While some weeds are edible (purslane, nettles, dandelions), many are a nuisance and compete with your chosen plants for water and nutrients.
     
    Whichever variation of “One year’s seeds makes seven years’ weeds” you prefer, the truth remains: a key part of weed control is not letting them go to seed. For best results, work on removing weeds before they are able to propagate. Hand pulling and hoeing are effective methods for killing many common weeds.
     
    Knowing what kind of weeds you have can be helpful in choosing the best management method. If you want to know what a weed is called or how it propagates, check into online resources or UC's Weed Gallery. If they propagate by seed, pull or hoe them before they flower and go to seed. If they re-grow from roots, pull up as much of the root as possible. Many weeds, like Bermuda grass, have multiple ways of multiplying. Only non-propagating parts are advisable to throw in the compost bin.
     
     
    - February, March, April, May, June, July, August, Any month
  • Pruning Roses to Minimize Disease -

    A chemical-free way to keep roses healthy and minimize disease associated with foggy summer mornings is to prune to improve air circulation.

    Roses pruning photo from University of Illinois
    Make sure you wear gloves to protect your hands from thorns and use clean, sharp tools. First, remove dead and diseased parts. Then remove anything that is growing where it doesn’t belong. This includes suckers below the graft union and branches that are crossing or growing towards the middle of the plant. Finally, prune for shape and health. Cut back to about four or five evenly-spaced strong canes, leaving a few buds on each cane. Make pruning cuts ¼ inch above outward-facing buds in order to create a vase shape that allows for good air circulation. Good air circulation allows the morning dew to dry and helps prevent rust and powdery mildew. 

    More Information: Rose Pruning

    - January, February, March, April, December
  • Sheet Mulching - "Lose the Lawn" -

    An easy and environmentally friendly way to "lose the lawn" is to smother the grass and mulch at the same time. Place cardboard or several layers of newspaper over the area, overlapping by eight inches to keep weeds from finding openings. Wet the cardboard or newspaper, then cover it with 4-6 inches of compost, plant trimmings, or other mulch. Having wood chips on top will give it a neat appearance. The materials will gradually break down and improve the soil over time. New plants can be installed by cutting an X in the cardboard or newspaper and placing the plants right through the mulch. UC Davis Arboretum Horticulturist Stacey Parker's website shows you how it's done.

    - March
  • Shovel Pruning -
    Sometimes a plant just isn’t working out in your garden and it comes time to part ways. The most drastic form of pruning is “shovel pruning” where you finally just dig the plant out. Another term for this technique is “editing the garden.” Perhaps you saw a plant you liked in another part of the country or world. If that other location had a different climate or soil type, it may not translate well to sunny, dry California with our clay soils. Perhaps you want to garden organically but the plant has too many pests or diseases and you are having trouble controlling them with organic methods. Or maybe it simply doesn’t resemble what the tag promised. It’s okay to let go. Spring and Fall are good times for new plantings, so it is also a good time to reassess the appropriateness of what’s in your yard.
     
    More Information: Shovel Pruning
     
    - March, September
  • Raised Beds -
    Raised beds make gardening easier in several ways. You don’t have to bend over as far to reach the surface. You can add any soil blend you like and you won’t compact the soil around the roots by walking on it. You can also better protect the roots and plants from critters. You can build them with wood or cinder blocks or anything that doesn’t have chemicals that can leach out into your food, for example, no pressure-treated lumber or railroad ties with creosote. If you’re using wood, redwood and cedar are the most resistant to pests and rot. You can be particularly green by using old fence boards or decking. Locate the beds where the plants will get the sun they need. Make sure the width is not more than twice your arm length so that you can easily reach all parts from the sides. To prevent gophers and other pests from tunneling into the root area, line the bottom of the bed with hardware cloth.
     
     
    - March, April
  • Frost Dates -

    The first and last frost dates for Santa Clara County are November 15 and March 15. These are important—but approximate—dates for gardeners to remember.

    • First frost date—this is the earliest date you should expect frost to occur. If you have plants that need to be brought in for the winter, or crops you need to pick before frost, this date will be important to you.
    • Last frost date—after this date, you wouldn't expect any more frosts. It's generally used as a milestone when planting outdoors, or pruning frost sensitive plants (such as citrus where you don't want to stimulate delicate new growth until danger of frost is past).

     

     Also see: Frost—Avoidance and Dealing with Damage

    - January, February, March, November, December
  • Leafy Salad Plants -
    Harvest your leafy vegetables early and often. Many leafy vegetables will bolt (go to flower) quickly if not harvested. When you harvest lettuce or similar greens, remove only the outer, older leaves. New leaves will continue to grow from the center and you'll be able to eat salads all winter long. Harvest head lettuce all at once when the head is full and firm.
     
     
    - January, February, March, November, December
  • Flowering Vines -
    Vines are plants that climb or sprawl and can easily outgrow their spaces if not pruned annually or more often. Many are pruned in the winter when they are dormant. This reduces shock to the plant and allows you to better see the structure when pruning. If the vines are flowering, wait until after the blooms have finished. Some vines get cut back almost to the ground to renew them. Some are cut back to the beginning of the herbaceous growth, leaving the woody vines. Others are pruned simply for shape or size. The UC Davis Arboretum All-Stars brochure includes several flowering vines. All-Stars are plants that have been tested and proven to thrive in California. The brochure lists pruning needs. It also has photos, characteristics, and requirements of the plants if you are looking for new plants.  
     
     
    - January, February, March
  • Certified Arborists -
    Whether you prune your own trees or hire someone, it’s important that whoever does the job knows at least a little about tree anatomy, plant health, and the purpose of the plant (shade? privacy? fruit?). Knowing the difference between heading cuts and thinning cuts, how to locate a node to direct growth, and how to open up a tree for air circulation are all part of good tree pruning. An improper pruning job can stress the tree, spread disease, invite pests, and promote weak branching. These can lead to breakage, damage, and injury. The cheapest bid may end up costing more in the long run due to damage repair, lawsuits, and additional fix-it pruning. Take a class or read tree pruning guides if you want to do a good job yourself. If you hire someone, it is strongly recommended that you choose a certified arborist who has been specially trained and is insured. The International Society of Arboriculture can help you find a certified arborist in your area.
     
    More Information: Tree Pruning Guide
     
    - January, February, March, December

2. What to plant

  • Selecting Seeds -
    While curled up inside the warm, dry house poring through seed catalogs, how do you decide among all the delightful descriptions? First, be clear on the purpose of your garden. Are you trying to grow exotic food? Do you want to attract native butterflies? Are you interested in flowers you can cut and bring inside? Next, think about the conditions of your site. Is it warm and sunny or is there a lot of shade? Do you have heavy clay soil? Choosing seeds that do well in your area makes for healthier plants with less work. At this point, you have the parameters within which to choose what tickles your fancy. If you would like to save seeds in the future, then choose open-pollinated seeds, including heirlooms. Heirlooms are open-pollinated seeds that have been around for multiple generations. Otherwise, you can plant hybrids that have the best traits of their parent plants but will not reproduce true to type from saved seeds. Follow planting directions on the packet for the best results.
     
    More Information: Seed Saving
     
    - January, February, March, May, June, July, August, October
  • Growing Purple Carrots -

    If you only buy carrots at the supermarket, you may think that they are all orange. It is believed that carrots were originally purple, with orange becoming popular through Dutch breeding. Several colors are now available at Farmers’ Markets and by growing your own. Springtime is a good time to start carrots from seed. Transplanting is not advised because you can easily damage the roots which are the relevant plant part.  Loose soil is important so that the carrots will grow straight. Scatter the seeds over the soil with as thin a covering as possible, keep moist until germination, and harvest when the tops expand to a good size. The Master Gardeners have done germination and growing experiments with different varieties and soil blends. Covering seeds with a thin layer of vermiculite yielded the fastest and highest rate of germination. Carrots are slow to germinate and could take as long as 3 weeks. Thin to 2 or 3 inches apart. For growing, a soil blend of 1/3 compost and 2/3 soil produced higher-weight carrots than blends with half of the soil replaced with either sand or perlite.

    Some common problems are twisted roots from planting too close together, forked or deformed roots from clods and rocks in the soil, a hairy root from too much nitrogen and splitting from too much water.

    More Information: Growing Carrots

    - February, March, April, September
  • Peas -

    Photo: University of California
    Photo: University of California
    An old American tradition says that planting peas on St. Patrick’s Day will bring good luck at harvest time. But the best planting date actually depends on the climate where you live. Planting on St. Patrick’s Day in the northeast may lead to a second planting weeks later when frost gets the first batch. Yet in warmer climates like ours, we can plant weeks earlier and may even be eating peas from the garden on St. Patrick’s Day. (We can also plant them here in the fall.) You may want to soak the seeds overnight to help get them ready to germinate. They can be planted directly in the ground, about half an inch deep. Keep the seeds evenly moist until they start to sprout. Provide a trellis or some kind of support for the vertical vines if you are growing pole peas; bush peas can stand on their own.

    More Information: Peas
     
    - February, March, August, September
  • Sweet Peas -
    Hummingbirds
    Hummingbirds
    You have probably heard people use the "sweet peas" term incorrectly. In garden terminology, sweet peas are flowers. They are not edible and are poisonous. Edible peas, even if sweet in taste, are not correctly called sweet peas. Sweet peas are incredibly fragrant vining flowers that come in a variety of colors, mostly pastels. They are an annual flower so they must be planted again every year. You can sow seeds anytime during the winter for spring bloom. The seeds are hard and it can be helpful to nick them slightly before putting them in the ground. Sweet peas do best in full sun or light shade. The plants will decline when it gets hot outside and they will need to be removed. Remember, you cannot eat sweet peas.  
     
    More Information: Sweet Peas
     
    - February, March
  • Tomatoes and Peppers -
    February and March are when Master Gardeners start seedlings for our annual Spring Garden Market. Tomatoes and peppers need a long, hot growing season, so starting seeds indoors or in a greenhouse in February or March will give them a head start. Put the seeds into small pots with loose potting soil and cover with a thin layer of soil or vermiculite. Keep them moist until they germinate. Keeping them in a warm place, such as by a sunny window or on a seedling heating pad, will help in germination. Provide plenty of light, preferably with fluorescent lighting close to the plants. As they grow and while waiting for the ground to warm up, they can be up-potted to larger pots and gradually introduced to the outdoors. Or, you can just wait until the Spring Garden Market and buy the seedlings we already started for you.
     
    More Information: Vegetable Gardening
     
    Photo: Tomato and pepper seedlings under adjustable-height fluorescent lights, by Laura Monczynski
     
    - February, March
  • Thyme -
    Thyme is much more than an herb to season food. In ancient times it was brewed by Egyptians for mummification, bathed in by Greek soldiers for courage in battle, and used by the Sumerians as an antiseptic and antifungal. And if you want a real surprise, check out the active ingredient list on a bottle of Listerine mouthwash. In your own garden it can be used for culinary purposes or as a purely ornamental landscape feature. It grows best in well-drained soil and sunshine, although it will tolerate some shade. It is quite drought tolerant once established. Common/garden thyme (Thymus vulgaris) is an excellent all-purpose thyme, growing to a foot tall and up to two feet wide. Lemon thyme (Thymus citriodorus), with its lemon scent, makes a nice evergreen border. Creeping thyme (Thymus serpyllum) stays short and can be used as a ground cover or between stepping stones. Thyme is attractive to butterflies and bees. 
     
    More Information: Growing and Using Thyme
     
    - March, April, May, June, July
  • Herbs -
    Many herbs can be grown both indoors and out, in pots or in the ground. Rosemary grows large and needs to be in the ground or a big pot. If you use basil to make pesto, you may want a row of it in the garden. Yet most herbs tend to be used in small quantities for seasoning and so they can be grown in small containers. They can be on the kitchen counter or a windowsill for ease of use in cooking. They can be on a patio if you are in an apartment or condo. And they are well suited to container gardening outdoors. Woody herbs can be grown from cuttings, lemongrass can be started from stalks from the store, and most others can be started from seed. After harvesting, many can be dried as well as used fresh.
     
    More Information: Growing Herbs
     
    - March, April, May, September, October
  • Seed Viability -
    Seed packets have a “packed for” date on the back. Yet seeds can still be viable for years beyond that date if stored correctly. Ideal storage conditions are cool and dry. The older the seeds are, the lower the germination rate will be. So plant more of the older seeds than the number of plants you ultimately want. You can do a germination test by putting seeds on a damp paper towel and enclosing them in plastic to keep them uniformly moist. Do this right before planting time so you can transplant the ones that successfully germinate. Or you can take your chances and just plant them directly and see what comes up. If you are saving your own seeds, make sure to choose seeds from the healthiest plants.
     
    Whenever it's hard to find flower seedlings, if you have some old flower seed packets, you can scatter the seeds randomly in a section of your yard and enjoy whatever flowers.
     
    More Information: Vegetable Seed Viability
     
    - January, February, March, April, May, August, September, October
  • Asian Vegetables -
    You can easily grow some vegetables used in different types of Asian cuisine and found in Asian markets. They are not necessarily native to Asia but have found their way into various cuisines. One way to decide which food to grow yourself is to choose varieties that aren't readily available or are more expensive in your local markets. It’s also fun to impress your family, friends, and neighbors with something they may not have seen growing before. Possibilities include sesame seeds, bitter melon, daikon radishes, gai choy, and opo. You can start cruciferous vegetables such as bok choy and Napa cabbage from seed now.
     
    More Information: Asian Vegetable Varieties
     
    - February, March, April, May, June, September, October
  • Plant Asparagus Crowns -

    Asparagus crowns can be planted now. Dig a trench eight to twelve inches deep, mix in fertilizer at the bottom and cover with two inches of soil. Set the roots in the trench about 18 inches apart, and cover with two inches of soil. Gradually fill in the trench as the plants start to grow. Asparagus is a perennial vegetable that will produce for several years. It's best to wait until the second year to harvest to let a strong root system develop for long term production. For more information, read UC Davis' Growing Asparagus in the Garden.

    - January, February, March
  • Attracting Bees -

    Bees are pollination workhorses, increasing garden production. Many plants will not produce fruit unless flowers are pollinated. Colorful annuals, such as Cosmos, edible African Blue Basil, and Salvias attract bees. You can also allow herbs and other plants to flower to create bee-friendly landscapes.

    The University of California at Davis has a garden dedicated to bees. The Honey Bee Haven website has more resources, including a list of plants they grow.

    - March, April, May, June, September, October
  • When to Plant Cool-season Vegetables -

    In Santa Clara County, cool-season vegetables such as beets, Cool season leafy vegetablesradishes, peas, arugula, bok choy, chard, collard, lettuce, mustard greens, broccoli, cabbage, and spinach, can be planted in very early spring for early summer and harvested before they bolt (go to seed), or in late summer for harvest in winter. Use our Vegetable Planting Chart as a planting guideline.

    Cool-season vegetables grow well in temperatures ranging from 55°F to 75°F. Take a good look at your garden to determine the best areas for planting, remembering that cool-season vegetables need 6-8 hours daily of sun. 

     

    - February, March, April, September, October
  • Starting Warm-Season Vegetables -

    Starting your own seedlings is fun, easy and can please your taste buds, too! You can select vegetables that are grown for a particular flavor such as heirloom varieties, many of which are not offered in garden centers. You can successfully start some vegetables (tomatoes, peppers, eggplants) from seed for transplanting this summer season. If seed starting isn’t for you or it is too late for you to start with seeds, consider buying transplants from our Spring Garden Market in April.

    There are two ways to start your seeds: direct sow straight into your garden or indoor sow. Direct sowing is easy for some plants such as peas and beets—see our Vegetable Planting Chart for more vegetables suitable for direct sowing now. Tomatoes, eggplants, and peppers are best started indoors and then planted in the ground after they are developed and sturdy. New plants and seedlings started indoors need to be hardened off. See Hardening off Seedlings before you plant them in the ground.

    Three factors influence germination: water, temperature, and light. Information found on the seed packages will show which conditions are best for germination. Peppers in particular germinate best with high soil temperature. Using a heating pad is one way that this can be done indoors.

    When reusing pots for seed starting, prevent the spread of plant diseases by making sure they are clean. Remove any remaining soil and cobwebs; then clean with a 10% bleach solution: 1 part bleach to 9 parts water.

    If you started seeds earlier in the year and they're outgrowing their pots, March may be a good time to move them into larger pots. Don’t try to plant them outdoors until after the soil reaches 65°F for healthy growth (and nighttime temperatures over 55°F). The soil temperatures outside are still too cold in March for planting summer vegetables in the ground.

    When transplanting, be sure to read packet directions for planting depth, spacing, and sun requirements for the best results.

    - February, March, April
  • Vegetable Planting Chart -
    Wondering what vegetables can be planted now? To get the best success—whether planting from seed or transplants—refer to our Santa Clara County Vegetable Planting Chart. It's based on our own garden experiences.
     
    - February, March, May, June, July, August, October, Any month
  • Flowers To Attract Beneficial Insects -

    Certain flowers help attract natural enemies of pest insects in the garden. Tiny wasps that parasitize certain insect pests or their eggs need pollen and nectar to survive. Predatory insects (syrphid fly larvae, lady beetles, lace wings, and many others) and mites survive on pollen and nectar from flowers when pest populations are low, and some feed on pollen in order to reproduce.

    Most of these beneficial insects are small, and so the best flowering plants to include in the garden are those that have small flowers that have pollen and nectar easily accessible and that bloom throughout the season. Avoid flowers that are difficult to weed out when they reseed.

    Many flowers that attract beneficial insects are easy to start from seed and this month is a good time to start them – some indoors any time or outdoors later in the month after frost danger has passed. Examples include sunflowers (try dwarf varieties like ‘Sunspot’ for smaller spaces), calendula, cosmos and many herbs like dill, basil and borage.  

    Other flowers and herbs that attract beneficial insects are easier to buy as plants. A few examples that can be planted this month are coreopsis, asters, and thyme.

    Reference info:
    UC Pest Note on Biological Control and Natural Enemies of Invertebrates
    UCCE notes on Attracting Beneficial Insects to Your Garden.

    - March
  • Plants to Attract Butterflies -

    Butterfly populations fluctuate in response to climate and habitat conditions. Many have specific host plants on which they feed and breed. Some common plants for attracting butterflies are milkweed, lantana, buddleia, and zinnias. For an extensive list of relationships between specific butterflies and host plants, see Art Shapiro's Butterfly Site at UC Davis.

    - March, April, May, June
  • Bare-Root Fruit and Nut Trees, Berries and Grapes -

    March or April is an excellent time to add bare root fruit and nut trees, grape vines, and bramble fruits to the landscape. These perennial edibles can provide decades of food production with a minimal investment of time and money. For more detailed information on specific varieties, take a look at the UC Backyard Orchard website.

    - March, April

3. Pests and Diseases

  • Rats -

    Have you found snail empty shells stashed in out of the way places, hollowed out Navel oranges, Meyer lemons with no skins, tomatoes with bite marks, fruit with holes gnawed in them or grape skins or cherry tomato skins scattered around? This could indicate the presence of rats. The UC IPM Pest Note on Rats provides a wealth of scientific information.

    Rats show up when your citrus, tomato or fruit first start to ripen. Rats are agile climbers and usually live and nest in shrubs, trees, and dense ground cover like ivy. Good sanitation is required. Garbage and garden debris should be eliminated. Use tight fitting lids on garbage cans. Thin out dense vegetation to make the habitat less desirable. Mow ivy once a year to the ground. Climbing ivies on fences or buildings should be removed.

    Trapping is the safest and easiest method for controlling rats. The simple snap trap is effective. The most important thing about trapping rats is to have lots of patience and keep trying. Wet some oatmeal enough for it to hold together, add dog or cat kibble or bits of lightly cooked bacon mixed in. Tie a walnut to the trigger and add a dab of peanut butter.

    Other baits to try are peanut butter and fresh fruit, but try to have something tied to the trigger. Set traps where rats are likely to travel or where you see droppings along fence lines or buildings. Bait the trap but do not set it for several days. Try different baits in multiple traps until you find one the rats like. Put two traps facing each other. After the rats are accustomed to being fed, then set the traps. If the rat springs the trap but doesn't get caught, move the traps to a different place and change to different baits. Rats prefer secluded spots and will be less wary there. Be sure to secure the trap with a wire or nails. Above all be patient and use multiple traps.

    - March, April, July, August, September, Any month
  • Citrus Pruning and Care -

    Once the threat of frost is past (typically March 15), it's a good time to cut back branches that touch the ground, fences, or other structures. Thin the tree to let more air into the middle. Trim out crossing branches and anything that looks dead.

    Pruning is not needed for fruit productivity yet may be desired for size management. Pruning will also help control scale and aphid infestations. If you see ants in the tree, use a sticky goo (such as Tanglefoot) on the trunk to keep them out of the tree. Be sure to apply the goo on top of tape rather than directly on the trunk. The ants 'protect' the scale and aphids. If you see scale (bumps on bark), thoroughly spray with horticultural oil to suffocate them.

    Yellowing of leaves is normal this time of year as the iron that keeps the leaves green is chemically unavailable because the soil is too cold. When the soil warms up (over 60° F), check for yellowing. You may not need to apply a nitrogen fertilizer if the new leaves are green.

    Refer to the UC Home Orchard web site for more Citrus Care information.

    - March
  • Snails and Slugs -

    Snails and slugs are patrolling your garden right now looking for new growth. Our preferred non-toxic method for dealing with them is to handpick early in the morning, or at night by flashlight. They can be saved for your friends with chickens, or crushed in place. If you do use snail bait, those made with iron phosphate are not toxic to pets and wildlife and they work well enough. For a full run-down of which management methods work, see the UC Pest Note on Snails and Slugs.

    - February, March, April, June, October
  • Camellia Petal Blight -

    Blossom damaged by camellia petal blightCamellias provide beautiful blooms in the spring. If any blossoms turn brown and mushy and fall to the ground, remove them immediately to halt the spread of a disease called petal blight. Don't put camellia leaves or petals in home compost if you plan to use that compost around your camellia plants. See UC Pest Note on Camellia Petal and Flower Blight for further information.

    - March
  • Brown Rot on Apricot and Peaches -

    Brown rot apricot fruit mummy. Photo by WW. Coates, UC Cooperative Extension.If your apricots or peaches had brown flesh last year, especially in the part surrounding the pit, they were probably infected with brown rot. It's a common fungal disease of stone fruit. You can spray with a copper spray at pink bud stage. A more important means of control is to remove affected fruit as soon as you notice it. The UC Pest Note on Brown Rot has more information.

    - March
  • Brown Marmorated Stink Bug -

    Native to Eastern Asia, this pest was introduced to the United States in the 1990s and has been established in Santa Clara County. Some features to distinguish these bugs from other stink bugs are white stripes on the antennae, a blunt head shape, and smooth shoulder margins.

    They feed and reproduce on a variety of plants and are particularly damaging to fruit. You can cut cosmetic damage off fruit and still eat the rest of the fruit. To keep out stink bugs, cover vegetable plants with row covers. You can pick the bugs off plants and squish them or knock them off into soapy water. They are attracted to light and can get into homes where if vacuumed up, they can stink up your vacuum bag.

     
    - March, April, May, June, July, August, September
  • Mosquitoes -
    Make sure you don’t have any water sitting around from our late rains. Mosquitos breed in standing water and can pass along deadly West Nile Virus to people. Check and dump water from any buckets, pots, saucers, dishes, or wheelbarrows. Put containers away or turn them over to avoid collecting additional water. Keep chemicals balanced in swimming pools. Ponds, fountains, and bird baths can also be breeding grounds. Add mosquitofish to these bodies of water to eat mosquito larvae. They are an environmentally friendly means of control and are available free of charge from Santa Clara County Vector Control.
     
    More Information: Mosquito Management
     
    - January, February, March, April, May, October, November, December
  • Dormant Oil Spray -
    Fruit trees and other deciduous woody plants can be treated with a dormant oil spray in the winter. The oil coats insects that “breathe” through their skin and suffocates them. Horticultural oil is generally accepted for use in organic gardening and considered safe for humans and wildlife. It should still be used only if pest problems have been observed. Aphids, mites, and scale can be controlled with this treatment. Spray liberally on branches where problems are evident. Make sure to complete the spraying before the trees start to bud and blossom so as not to damage developing flowers and fruit.
     
     
    Photo: San Jose Scale, by Jack Kelly Clark
    - January, February, March

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