By Brent McGhie, Butte County Master Gardener, October 4, 2013
As days shorten and temperatures cool, the pace of gardening slows along with plant growth. But there is still plenty to be done during the fall and winter months. In fact, much of what is done in the garden now will set the tone for the following year.
Cleaning up the garden is an important chore. Remove any dead plant material from the garden and add it to your compost pile. Pick up any fallen fruit from around fruit trees. These actions will eliminate habitat for overwintering diseases and pests. Rake up leaves. Matted leaves left on a lawn can suffocate it. Instead, add your leaves (chopping up the largest ones) to your compost pile. If you delay dead-heading your spent flowers and seed heads until early spring the birds will appreciate having this extra source of food during the lean winter months.
Prune deciduous trees and shrubs during their dormant period. However, it is worthwhile to do a little research on each plant to become familiar with its pruning requirements. For example, pruning early-flowering plants such as azaleas, flowering quince, or forsythia in the fall will remove flower buds and reduce the spring flowering display. If these plants require pruning, it should be done just after they have finished blooming.
Consider planting a winter garden. Radish, spinach, pea and onion seeds can be planted in October or November. Cauliflower, broccoli, lettuce and turnip seedlings can be planted in November. If you don’t want a winter garden, clean up your summer garden and mulch it with straw, grass clippings or chopped leaves. Mulch will discourage weeds and provide soil nutrients for next year’s garden.
Planting bare root trees and shrubs during their winter dormancy allows healthy root systems to develop before budding out in the spring. Fall is also the time to plant bulbs and perennials. Squirrels can notice disturbed soil and may dig up tulips and other bulbs. Disguise your work by flooding the soil surface with water and then covering the soil with mulch.
Renovate garden beds by weeding, adding organic matter, and tilling the soil to a depth of at least six inches. Refresh existing mulch around established plantings.
Conduct an irrigation review and adjust your watering schedule to reflect the lower water requirements of fall and winter. Make any repairs (such as fixing broken pipes, hoses, or damaged sprinkler heads) before spring. If you have an automatic system, be sure it is operating correctly.
If you plan to create new garden beds, fall is a good time to do it before you are faced with the rush of spring gardening jobs. And if you plan on creating a new bed in an existing lawn area, a good method is to cover it with a thick layer of newspaper topped with a layer of mulch. This will kill the lawn (as long as it’s not a dormant perennial like Bermuda grass) and the bed will be ready to be worked in early spring without the effort of manually removing the sod.
Finally, clean and sharpen your tools. Keeping tools clean helps prevent the spread of disease and prolongs the life of the tools. If you prune diseased plants, disinfect clippers, loppers or saws with a diluted bleach solution, blot them dry, and then apply a light coating of oil. Sharp tools produce clean cuts and clean cuts heal more quickly. If you have empty flower pots that you are planning to reuse, clean them by removing dirt with a coarse brush and then rinsing with water. Let terra-cotta pots dry completely before storing them.
By Brent McGhie, Butte County Master Gardener, September 20, 2013
To grow, plants must absorb nutrients from the soil. Not only must these nutrients be present in sufficient quantities, they must also be available for uptake by the plant. Nutrient availability is primarily determined by soil texture and pH. Soil texture is the amount of sand, silt, clay and organic matter in the soil. Soil pH is a measurement of the degree of soil acidity or alkalinity; this measurement has the greatest effect on nutrient availability in the soil.
pH is measured using a scale from 0 -14, with 0 being the most acidic, 7 being neutral and 14 being the most alkaline. Most plants grow best in a pH range of 5.5 to 7.5 (medium acidity to very slightly alkaline). In this pH range, essential nutrients are available in chemical forms that plant roots can absorb. At higher or lower pH levels, some nutrients form solid precipitates that cannot be dissolved in water, and thus are not available for absorption by roots.
Soil pH can also affect the solubility of harmful mineral elements. For example, in very acidic soils (low pH) the essential elements of nitrogen, phosphorus, potassium, sulfur, calcium magnesium, and molybdenum may be unavailable, while toxic levels of aluminum and manganese might be present. Soils with high alkalinity can reduce availability of nitrogen, phosphorus, iron and manganese resulting in deficiencies, and they may contain excessive levels of soluble salts or sodium, both of which are harmful to plants.
When a soil’s pH is too low (acidic) it can be adjusted upward with the addition of wood ashes or lime. Some forms of lime that can be added to the soil include calcium carbonate, calcium hydroxide, calcium oxide, or dolomite. Sulfur is used to lower the pH of alkaline soils (those with pH above 7.5). Elemental sulfur, gypsum, ammonium sulfate, and Epsom salt are sources of sulfur normally available for purchase.
Here in Butte County, low soil pH is most likely to be encountered in the foothill areas including Paradise, Magalia, east Oroville, and Forbestown. There are limited areas on the valley floor near Gridley and Biggs, and on the south and west margins of Durham and Chico where more alkaline soil conditions (above pH 7.5) are found. If you feel that pH and nutrient availability may be an issue in your garden soil, it is a good idea to have the soil tested. Simple pH test kits are available in garden stores; alternatively, soil samples can be analyzed by commercial Agricultural Laboratories, which can be found listed in the yellow pages of the phone book under Laboratories-Analytical, or in online directories.
Soil texture affects the soil’s ability to retain water and nutrients. Generally speaking, soils with large amounts of clay or organic matter tend to hold water and nutrients more effectively than sandy soils. Sand does not hold nutrients very tightly, so as water drains through sandy soil, it tends to carry nutrients along with it. This process, known as leaching, carries nutrients out of the root zone and makes them unavailable to plants. Clay, on the other hand, has the ability to attract and hold nutrients in the soil and thus fewer nutrients are lost when water drains through clay soils. However, too much clay in the soil can cause other problems. For example, clay soils have a tendency to be waterlogged during wet weather and rock hard when they dry out.
If a soil has too much sand or clay, the most cost-effective remedy is to add organic matter. Organic matter in the soil mimics the positive effects of clay (improved water and nutrient retention) without the disadvantages. Organic materials are most effective when the soil is amended at least 30% by volume. The effect of adding organic material is not permanent because it decomposes with time. Coarse materials decompose more slowly and last longer in the soil. Also, organic material should be composted before incorporating it into the soil because microbes feeding on uncomposted material can actually remove important nutrients from the soil.
By Brent McGhie, Butte County Master Gardener, September 6, 2013
What do those numbers on bags and boxes of fertilizer and soil amendments really mean? And what is the difference between a fertilizer and an amendment?
Whether a material is considered an amendment or a fertilizer depends on its effect on plant growth. Amendments, such as peat moss or leaf mold, affect plant growth by conditioning the soil. Fertilizers, on the other hand, influence plant growth by improving the supply of available nutrients in the soil. Many organic products (for example steer manure), act as both amendments and fertilizers because they fertilize the soil with nutrients and amend it with organic materials which improve soil tilth and water retention.
All commercial fertilizers are labeled with three bold numbers, indicating the percentage of primary plant nutrients that they contain. The first number is the percentage of nitrogen (N), the second number is the percentage of phosphorus (P - in the form of phosphate, P2O5) and the third number indicates the percentage of potassium (K - in the form of potash K2O). Nitrogen, phosphorus and potassium (N-P-K) are the primary nutrient elements needed in the greatest amounts by plants. Therefore, a bag of 15-10-6 fertilizer contains 15% nitrogen, 10% phosphate and 6% potash.
Nitrogen is an important component of proteins, enzymes, chlorophyll and DNA. It is essential for photosynthesis, plant metabolism, and many growth and development processes. Symptoms of a nitrogen deficiency in plants may include slowed growth; pale, yellowing leaves (a condition called chlorosis); and the tips and margins of older leaves turning brown and dying. Because they tend to be heavy “feeders,” many vegetables other than legumes (beans and peas) are prone to this condition. Nitrogen deficiency can be addressed by amending the soil with manures, which are high in nitrogen. Of manures, chicken manure generally has the highest nitrogen content, at 3-5-1.5. Other organic fertilizers with high nitrogen content are blood meal (13-2-3) and fish meal (10-6-0).
Phosphorus is a constituent of proteins, cell membranes, enzyme systems and DNA. It is essential for energy systems and photosynthesis, and stimulates root and seed formation. Abnormally dark green, purple, or bronze foliage is a symptom of a phosphorus deficiency, as is browning along leaf margins. A phosphorus deficiency may also result in poor fruit or seed development. Phosphorus deficiency is relatively uncommon, but grasses, carrots, lettuce, spinach and apples are plants that seem to be more highly susceptible. Here, too, chicken manure is a good organic amendment, as it is high in phosphorus, while bone meal (4-23-0) is the organic fertilizer containing the greatest amount of phosphorus.
Potassium is necessary for transport of materials across cell membranes, the opening and closing of leaf pores, the movement of water and sugar up and down stems, the division of cells, and the manufacture of starches and proteins. It also improves the size and quality of fruits and increases disease resistance. A potassium deficiency causes leaf tips and margins to curl upward, brown and die, starting with older leaves. Plants may have weak stems that fall over, or “lodge,” and may have poor fruit or seed development. Among vegetables and fruit crops, this deficiency is most common in potatoes, broccoli, tomatoes, apples and raspberries. It is also common in almonds and prunes in Butte County. As a soil amendment, steer manure (1.5-1-2.5) has slightly more potassium than chicken manure. Wood ashes (0-2-6) are high in potassium, but are highly alkaline and should be used with caution. Other organic fertilizers containing potassium are blood meal and cocoa shell meal (3-2-3). It should be noted however, that cocoa shell meal can be toxic to dogs and other animals and should be avoided by pet owners for this reason.
In addition to nitrogen, phosphorus and potassium, other elements may be listed on fertilizer labels. It has been established that there are 14 other essential elements necessary for plant growth. The secondary nutrients (those needed in smaller quantities than N, P and K), are calcium (Ca), magnesium (Mg) and Sulfur (S). Micronutrients, needed in trace amounts by plants, are boron (B), chlorine (Cl), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), nickel (Ni) and zinc (Zn). All of these nutrients (including N-P-K) are taken up by plant roots only when they are dissolved in soil water. Three final elements, carbon (C), hydrogen (H), and oxygen (O), are supplied through the uptake of air and water by the plant. Carbon is absorbed through pores in the leaves (stomata) in the form of carbon dioxide (CO2), while plants obtain hydrogen and oxygen from the breakdown of water (H2O) during the process of photosynthesis. Although plants need much higher concentrations of primary and secondary nutrients, all 17 essential nutrients must be available for healthy plants.
Source: Dennis R. Pittenger, California Master Gardener Handbook (Oakland, CA: University of California, Agriculture and Natural Resources Communication Services, 2002).
By Michelle Ramsey, Butte County Master Gardener, August 23, 2013
The scary-looking, ominously-named wolf spider is actually a beneficial insect. Wolf spiders belong to the class Arachnida andare members of the family Lycosidae (derived from the Greek word lycos, meaning wolf). Wolf spiders stalk their prey like wolves do; they do not spin webs or use silk to subdue prey. They are fast-moving, aggressive ground predators with excellent eye sight (helped in no small part by the fact that they have eight eyes, arranged in three rows: the first row has 3 small eyes, the second has 2 large eyes and the third row, closest to the top of the head, has 2 medium-sized eyes). They are nocturnal and hunt for insects mainly at night. They are likely to be found on the ground in open areas like farm fields and grassy environments, or harboring in ground tunnels, amidst pieces of firewood or debris. There are more than 2000 wolf spider species, with body sizes ranging from less than one millimeter to 30 millimeters (.04 to 1.2 inches).
Wolf spiders provide natural control of harmful insects. The Carolina Wolf Spider (Hogna carolinensis) is the largest of the wolf spiders. It is brown with black markings. Its body can measure more than one-inch long (and the whole spider can measure 4 inches across, from legs to legs). Female wolf spiders are larger than males; their undersides are solid black. Because some wolf spiders are large and hairy, they are sometimes mistaken for tarantulas.
Wolf spiders are not known to be aggressive but will bite if provoked or threatened. Their bite is not considered dangerous to people but it can be painful (like a bee sting). When disturbed, they will retreat very quickly.
Young wolf spiders hatch from eggs and look like tiny adults. They shed their skin as they grow. Males reach maturity from spring to summer. Mating occurs in autumn and the males die before the winter begins. Females lay eggs soon after mating. They carry their egg sacs in a silk cocoon attached to their abdomen by spinnerets. The spiderlings hatch in June and July and attain only half of their full size by the following winter. After hatching, the spiderlings cling to the mother’s body for about a week before detaching. They too will overwinter and complete their growth the following spring and summer. Female wolf spiders may live for several years. It is common to find females carrying their young spiderlings on their backs during the summer months. They can be a common pest in the fall when they begin to seek shelter from cooling temperatures.
The wolf spider is a solitary creature, preferring to live and hunt alone. Most are wanderers without a permanent home; however some Carolina wolf spiders create deep tubular burrows to live in. While wolf spiders prefer to live outdoors on the ground, they may occasionally wander indoors, where they might be found around doors and windows, and in garages. They may be seen running across the floor when disturbed. To keep spiders out of your home, seal cracks, gaps and other openings. For immediate and long-term control of wolf spiders, physical removal and/or destruction of the individual spider may be the best control.
For further information visit: http://www.ipm.ucdavis.edu/QT/commongardenspiderscard.html
By Brent McGhie, Butte County Master Gardener, November 29, 2013
There are several advantages to planting bare-root trees: they are usually less expensive, easier for gardeners to transport, and they will grow their roots entirely into native soil (rather than having to transition from potting mix into dissimilar native soil). Also, the ideal time to plant bare-root trees is in the winter, when you have a break from the demands of other garden chores.
Bare root trees are usually available from December through February or March, but before purchasing a tree it's a good idea to select an appropriate planting site and properly prepare it. Choose a site with plenty of sun. Fruit trees need at least 6 hours of sunlight per day; if a tree does not receive enough light, it will grow more slowly and set less fruit (plus, fruit that does set may be smaller and less sweet). Fruit trees also thrive in deep, well-drained soil. If soil is compacted, an area several feet wide around the planting site should be cultivated deeply to loosen the soil for root growth. Avoid adding fertilizer or soil amendments directly to the planting hole; instead, a well-decomposed compost can be worked into the planting site before digging the hole. Finally, if hardpan is present within one and one-half to two feet below the soil surface, it must be penetrated to allow proper drainage and root growth.
Once the planting site has been prepared, it's time to select the tree. Trees with a trunk diameter between one-half and five-eighths of an inch usually become established faster than larger or smaller stock. If the root mass is visible, be sure it is well balanced, not “one-sided.” Remove any dead or damaged roots before planting. It is best to plant bare-root trees immediately after bringing them home, but if this is not possible, the roots should be covered with sawdust or compost and kept moist until planting.
To prevent the tree from settling too low in the ground, dig the planting hole no deeper than the tree's roots. To encourage root growth, the hole should be about twice as wide as the spread of the roots. If the soil contains a large amount of clay, the sides of the hole should be scored to aid outward root growth. Build a cone of soil in the center of the hole and spread the roots over the cone, with the bud union (where the tree was grafted onto the root stock) facing south west. This prevents sun-scald of the flat side of the trunk just above the bud union. Next, back-fill the hole with the same soil that was taken from it until the hole is half filled and gently firm the soil to eliminate large air pockets. Double check the planting depth, making sure the bud union is four to six inches above the soil surface. Finish filling the hole with the native soil and gently firm it once again. When properly planted, the tree's uppermost roots should be just slightly below the soil surface and the soil should slope gently away from the trunk, preventing water from accumulating there.
Thoroughly water the newly-planted tree to settle the soil around the roots. Unless the tree has been planted in wet, heavy clay soil, a basin should be built around the tree. (In clay soils, keeping the soil too wet can eliminate air spaces in the soil, “suffocating” the roots). The basin should be donut-shaped, with the tree sitting in an island of soil in the middle of the basin. Again, to discourage rot, make sure water drains away from the tree. The basin should be slightly wider than the planting hole, ensuring that the entire root area receives water. After growth has begun in spring, water the new tree once or twice per week, adjusting the schedule as needed for cool rainy periods or early hot spells.
Clear an area about 3 feet wide around the tree, eliminating weeds and grasses to keep them from competing with the tree for water and nutrients. To prevent future weed growth and conserve moisture, a layer of mulch 3 to 6 inches thick can be placed around the tree. However, to avoid crown rot, keep the mulch several inches away from the tree trunk. As a final step, remove the top of the tree by pruning back to a single trunk approximately 24 inches tall and paint the bark of the entire tree trunk with white interior latex paint diluted with water (two parts water to one part paint) as a whitewash to reflect excess heat. This prevents sunburn and the resulting invasion of wood-boring insects that can stunt or kill the new tree.