The Digging Fork Nov Dec 2006

The Digging Fork A Davis Garden Newsletter November – December 2006 Planting see Plant notes

Seeding see Plant notes

Fertilize Pest & Disease Control Tasks

Water

November

December

Shrubs and trees Perennials Cool season annuals: Iceland poppies, stock, pansies, primroses, annual chrysanthemum, cyclamen, snapdragons Spring blooming bulbs: Darwin hybrid tulips, Dutch iris, daffodils, hyacinth, brodiaea and others. Too late to plant anemone and ranunculus. Vegetables: bulbing onions, garlic, broccoli, cabbage, cauliflower, lettuce Vegetables: peas, fava, lettuce, green onions, arugula, cilantro, spinach, Swiss chard, turnips, carrots, beets Flowers: larkspur, sweetpea, breadseed and Shirley poppies, nasturtiums, forget-me-nots

Purchase bare-root plants: ornamental and fruit trees, shrubs, berries, grapes and roses Go early for best selection. Many nurseries will hold purchases until you are ready to plant.

Spray nectarines and peaches at Thanksgiving for peach leaf curl. Watch for slugs, snails, Caterpillars. Control as needed. Cleanup, pick up leaves and compost them Cut back perennials (don’t cut back frost tender perennials until spring) Divide and plant perennials Dig and mulch Mark plants that die back completely Remove unwanted seedlings --or transplant After frost, pull out all summer annual flowers and vegetables Water as necessary, newly seeded areas especially. Turn off automatic sprinklers after first good rain.

Bare-root vegetables: artichokes, asparagus, rhubarb, strawberries Spring blooming bulbs: same as for Nov. Vegetables: fava, spinach, Swiss chard, cilantro Seed inside now for transplanting into the garden in February – cabbage, broccoli, lettuce and cauliflower

When pruning look for borer damage and cut off infected limbs

Finish November tasks Prune deciduous trees Can start pruning roses toward the end of the month.

(Have a nice holiday!!)

Water under large eaves

Dahlia photos taken by Patricia

Dahlias In October, dahlias are a spectacular sight. The show continues into November or until we get a frost. These tuberous roots from Mexico and Guatemala are easy to grow if you know a few tips. Plant them in March or April when they can be found in nurseries. Dahlias come in many types (formal, cactus, pompom, singles, doubles, etc.) and the flowers range in size from about 2” in diameter to about 10” or more! They like full sun, lots of organic matter and are planted with the top of the root 2” deep. When the leaves first emerge from the soil, they are usually attacked by snails, slugs and earwigs. If you don’t control these pests, the plant will keep trying to grow, but continue to get eaten. Once the leaves are 4-6 inches high the plant can usually outgrow the pest damage, but it is a good idea to continue to monitor and control as needed. The plants will start to flop over in the summer. If this is a concern for you, try putting a tomato cage over the plant when small to keep the stems upright as they grow. Blooming starts some time in the late spring to fall, depending on the variety. Snails and slugs like to eat the flower petals too. To bring inside, cut blooms when they are almost mature. If they are wilting, try searing the cut with a flame or plunging newly cut stems into very hot water and letting them stand overnight. The back petals, near the calyx often look bad and can just be pulled off. There is no need to dig up the roots each fall. After a frost, cut the stems to about 6” above the ground to help mark the plant location. Adding a plant label will help, too. In the early spring, make sure no other plants are covering the planted area. If you don’t see the plants emerge you won’t be able to monitor pest problems. They also emerge faster with the sun warming the ground. If you see an especially wonderful dahlia in your neighbor’s yard, ask for a division in the fall or early spring. When you dig the root, the new growth buds are on the base of the old stem, where it joins the root. Roots can be divided by cutting off a section of root with a new bud attached and planted right away.

Peach Leaf Curl Every spring gardeners venture into their garden eagerly waiting to see how their fruit trees are developing, hoping that this year they will be able to collect some fruit. However, it is all too common for many home gardeners to be disappointed when they see the leaves of their beloved trees turning red and puckered. Red, thickened new leaves are the first signs of the fungal disease Taphrina deformans, commonly known as peach leaf curl. Nectarines and peaches are susceptible to this disease. Sadly, once these symptoms are discovered on the tree it is too late to begin treatment for this season’s fruit development. The tree will most likely shed its red, puckered, distorted leaves and put on a healthier set, but fruit production will be greatly reduced. The tree, if left untreated, will develop symptoms next year and continue to decline. However, there are ways to control the fungus. Bordeaux mixtures (lime and sulfur), calcium polysulfide sprays, and fixed copper sprays used correctly will prevent symptoms of the disease from forming and allow fruit production the following year. The sprays must be applied at the correct time. The first time being after the leaves drop (usually late November) and the second time in the spring before the buds break. A third spray can be added around New Year’s. To be effective the copper spray must contain at least 50% copper. The important thing to know is once a tree has the fungus it usually has it for life. The spores survive our hot, dry summer and cover the whole tree until wet spring weather cause the spores to spread and develop on all parts of the tree. Spraying every year is necessary to control the disease. Pruning every fall also helps to control the disease along with picking up discarded leaves from under the tree.

Peach leaf curl can be a problematic frustrating disease but remembering these two or three important spray dates of Thanksgiving, New Years, and Valentine’s Day can allow you to have the bumper crop you have always wanted.

Future Garden workshops The two fall workshops on Vegetables for Cool Season and Fall Garden Cleanup and Planting have already happened but more workshops are planned for the next year. Workshops are held in Patricia’s 1 acre country garden. There is time to explore and ask lots of questions.

Pruning & bare-root planting (roses, fruit trees, etc.) Sunday, January 7 12:30-4:00 pm Back up date due to rain – Sunday, January 14 Vegetables for Warm Season Saturday, March 10 11-2:30 pm Back up date due to rain – Saturday, March 17 Spring Garden Cleanup and Planting May –date TBA

Plant notes! Here is more information about plants mentioned in this newsletter.

Abutilon or flowering maple Abutilon hybridum Semievergreen shrub. Attracts hummingbirds. Annual Chrysanthemum Chrysanthemum paludosum Breadseed or opium poppy Papaver somniferum Annual that reseeds. Edible seeds. Brodiaea Brodiaea California native bulb that doesn’t like summer water. ‘Queen Fabiola’ cultivar is the most garden friendly and will take summer water. Cyclamen Cyclamen hederifolium, hardy type and C. persicum, florist type. Bulb that blooms in winter, useful under deciduous trees. Summer deciduous. Dalhia see featured article Fava or broad bean Vivia faba Annual vegetable that fixes nitrogen in soil with the help of rhizobia. Forget-me-not Myosotis sylvatica Annual that reseeds. Iceland poppy Papaver nudicaule Grown as annual. Larkspur Consolida ambigua Annual that reseeds and is much easier to grow than delphinium. All parts of plant are poisonous!! Nasturtiums Tropaeolum majus Annual with edible flowers. Dwarf and climbing varieties. Onions, bulbing Allium cepa Bareroot plants can be found in some nurseries in Nov. Also look for 6-paks in Oct. Varieties that do well in Davis: ‘Stockton red, white and yellow’; ‘Walla Walla’ and ‘Red Torpedo’ Pansies Viola x wittrockiana Annual with edible flowers. Peas Pisum sativum Soak seeds overnight before planting. Two varieties to try ‘Sugar Snap’ and ‘Alderman’ (also called ‘Tall Telephone’) Primrose Primula polyantha Perennial that is often treated as annual. It does well under deciduous trees as they need summer shade. . Shirley or Flanders poppy Papaver rhoeas Annual that reseeds Snapdragon Antirrhinum majus Perennial that usually dies in a few years due to rust infestation. Stock Matthiola incana Perennial that gets woody and eventually declines. Wonderful fragrance!! Sweet pea Lathyrus odoratus Annual. Soak seeds overnight before planting.

The Sticky Truth About Scale Often friends will ask if their plant is sick because it is dripping ‘stuff’. Most likely their plant has a sucking insect that is taking the sugars out of the tree and what is dripping is the sugary excrement of the insect. Asked if there are insects present, they will insist that there are only ants on the tree. When asked if it looks like their plant stems have little bumps on it they say yes, but that they thought they were part of the plant. In fact these insects, known as scale, are excreting the sugar substance also called honeydew. Scale is a tough insect to get rid of. In its juvenile form the scale are mobile and easier to treat. When they reach maturity they lay down a protective shell and secure themselves to the plant. If a plant develops a large infestation of scale it could be harmed when the honeydew coats the leaves and prevents photosynthesis. Sooty mold, a black slightly fuzzy growth, can then form on the honeydew further halting photosynthesis. The plant will then turn yellow and start dropping leaves. If scale are present, chances are that ants are right there with them. The ants, who love the sugary honeydew, protect the scale and actually farm it. Scale can be treated, but it is tough. An IPM (Integrated Pest Management) approach is best. Pruning off of heavily infested limbs is recommended along with simply wiping the scale off if numbers are small. To control the ants that are protecting the scale from predators, apply a substance called ‘Tanglefoot’ around the trunk of the tree they are in. Make sure to apply 2” wide masking tape around the tree before applying the ‘Tanglefoot’. This makes it easier to remove once it is no longer sticky and effective. ‘Tanglefoot’ will only work if all modes of access to the tree are protected. Another way of controlling ants is placing ant stakes at the base of plants. Some ant stakes contain arsenic or boric acid (which is safer than arsenic). If these methods are not working, spray the plant with horticultural oil to kill the immature scale and over wintering eggs. This spraying should be done in the dormant season, preferably after a rain. For citrus, abutilon (a particular favorite of scale) or evergreen plants spray in cool times of the year. Be careful not to spray if scale predators are present, such as ladybugs or ladybug larvae.

Scale on citrus stems

More gardening tips! Buy chrysanthemums now when they are in bloom. Enjoy them in a pot for fall decoration then plant in the garden in a sunny spot to get flowers again next fall. This time of year we can’t think of being without a fan rake for getting leaves out of flower beds without damaging the plants. Two sources: Lee Valley Tools www.leevalley.com 1-800-871-8158 or Peaceful Valley Farm Supply www.groworganic.com 1-888784-1722. A favorite web site for pest and disease information: www.ipm.ucdavis.edu Plant labels help mark plants that die back to the ground, like dahlias and bulbs. Tall, fall blooming perennials like perennial sunflowers (Helianthus maximilianii) aster (Aster ssp.), boltonia (Boltonia asteroids), and chrysanthemum, tend to flop when they are ready to bloom. If you cut the stems of these plants to about a foot tall around the 4th of July they will bloom with shorter and more upright stems. Sometimes bloom is delayed a bit, however.

Newsletter created by: Marlene Simon -- UCD graduate in Horticulture Patricia Carpenter -- Garden Design and Education. 30 years of Davis gardening experience. The bi-monthly newsletter is free if received by email. If mailed, the cost is $6 per year. To be added to the subscription list or to unsubscribe, contact us at: [email protected] updated 12-20-06 Perennial sunflower