Fall Gardening Tips

Pruning a rose bush. (contributed photo)

The following are questions that are often asked during the year.

When can I prune my azaleas?

If the right azalea variety is planted in the right location, then pruning would rarely need to be done. Formosa azaleas can easily get 10′-15′ tall in time. Satsuki hybrids (gumpo varieties) generally get 3′ tall and 3′ wide. Picking the best plant for the location should be at the top of the list. If you need to prune your azaleas wait until after they flower but before the first of July. In July the azaleas begin to set the buds for next spring’s flowers, when pruning cut branches in the interior of the plant to a side branch. If you cut a 20-year-old plant completely down remember the plant still has a 20-year-old root system to put out new growth. Fertilize azaleas in March and while they are flowering.

When and how do I need to prune my roses?

When pruning roses, it depends on the type of rose you have. Do you have a shrub rose, hybrid tea rose, miniature rose or a floribunda rose? Most often you see hybrid tea roses planted in people’s landscapes. The drastic pruning of hybrid teas should be done in late winter or early spring just before buds break dormancy. Two-thirds of the growth can be removed to a side bud. Throughout the year you can prune to improve the shape; promote new, healthier growth; and eliminate dead, broken or diseased branches. This is also true for your knock-out roses too. Remember, in order to have healthy roses you may need to follow a continuous fungicide and insecticide spray program.

Which plants are good to use as screening plants?

 There are many plants that can be use as screening plants. The type of plant you pick is dependent on the location you want to plant it. The main question you need to consider is whether the plants will be in the sun or shade. A few shade-tolerant screening plants include; camellias, wax myrtles, cherry laurel, rhododendrons, and osmanthus. A few sun-tolerant screening plants include; abelia, Nellie R. Stevens holly, American holly, wax myrtles, osmanthus, ligustrum, cryptomeria (tree), and Eastern Red Cedar (tree).

When do I need to fertilize my lawn?

If you have a cool-season fescue lawn you will want to fertilize in February with one pound of actual nitrogen per 1,000 square feet. (The first number on the bag always represents the nitrogen content in the bag.)  For example, if you have a 10-10-10 fertilizer divide 100 by 10 and you will get 10. That means you need to apply 10 pounds of fertilizer for every 1,000 square feet of lawn. The other two times you need to fertilize cool-season lawns is in September and November. If you need to fertilize a warm-season lawn such as bermudagrass, fertilize with one pound of nitrogen after the grass turns green (April) and continue fertilizing through the summer. Centipedegrass has a different requirement than other grasses. It requires only 1/2 pound of nitrogen in June. If you have centipede and have questions about it give the Cooperative Extension Service a call.

Fruits of our Labor

Apple on a tree (contributed photo).

Many fruit-growing hobbyists neglect the annual maintenance of their fruit trees due to lack of time or they are not exactly sure how to take care of them. Without training or pruning, fruit trees will not develop proper shape and form. Properly trained and pruned trees will yield high-quality fruit much earlier in their lives and live significantly longer.

There are many factors to consider if you want to be successful when planting fruit trees. First, you must select the right type of fruit and the right variety for your area. Site selection is important because you need to consider soil type, soil fertility, air drainage, sunlight, and if there are nematodes present or not. These are all areas that the average person overlooks. Then, you also have to consider weed control, insect control, disease control, and believe it or not rodent control.

­The most common tree fruits grown here include apples, figs, peaches, pecans, and pears. Not all of these fruit trees have the same pollination requirements. Did you know that pecan trees are monoecious? This means that they have separate male structures, called catkins, and female flowers on the same tree. However, the time at which the male catkins release pollen is not the time at which the female flowers can be pollinated. Pecan trees are separated into two pollination groups referred to as Type I and Type II. Catkins on Type I trees release their pollen before the female flowers are receptive and catkins on Type II trees release their pollen after the female flowers are receptive. Because of this difference, both Type I and Type II pecan trees are required for pollination. To ensure maximum pollination and production, at least three varieties should be planted together.

Apples should be considered self-incompatible, meaning that they cannot pollinate themselves or any flowers of the same apple variety. The best quality fruit is harvested when cross-pollination occurs with a suitable pollinizer variety. You will need to plant at least two varieties of apple trees together in order to maximize fruit production and quality. Make sure that the varieties you choose have overlapping bloom dates, so that both varieties bloom at the same time. When choosing a peach variety, the main features to consider are the chilling requirement and the time of ripening. Varieties with less than a 750-hour chilling requirement should not be planted in North Carolina because of the risk of crop loss due to spring frosts or freezes. Figs can be produced in our area, however there are two limiting factors to their production. One being cold weather and the other nematodes. We can deal with the nematodes, but we cannot control the weather. Celeste and Brown Turkey are two fairly hardy fig varieties for our area.

If you would like more information about growing fruit trees, call Cooperative Extension at 919-496-3344.

Gardening in the Shade

Simply saying a plant will grow in the shade is too simplistic a statement because not all shade is the same. There is filtered shade, partial shade, open shade, and dense shade. Shade changes with the time of day and from year to year as trees grow. Sites that might be in full sun part of the year may become heavily shaded as the season changes or as trees leaf out. Light is also influenced by topography. For example, a south-facing slope receives more light than a north-facing slope.

Birdbath covered with pink flowers. (contributed photo)

Types of shade
Filtered shade is suitable for growing many plants — even plants that prefer full sunlight such as iris or daylilies. Light intensity is relatively high with sunlight and shade constantly changing from minute to minute during the day. Filtered shade occurs under birch, mimosa, and honey locust trees. Partial shade changes as the day progresses. The area may be in the shade until some point in the day the sunlight shines on the area. Open shade occurs where there are no trees overhead to block sunlight but the plants are in the shade due to the shadows of a building. Open shade is well lighted but does not receive direct sunlight. Deep shade is found in heavily wooded areas and in landscapes where large evergreens or broadleaf deciduous trees (maples, oaks, hickories, beeches) occur. Deep shade can also occur in a narrow side yard on the north side of the house when another building is located close by.

Many shade plants are native to wooded areas and grow best in soils exposed to decomposing leaf litter and compost. Moisture in shaded areas is different than sunny areas. The cooler temperatures and less exposure to wind decrease water loss. However, competition from tree roots and the large, tender leaves of many shade-loving plants can cause moisture shortages. Trees vary in their competitiveness for soil moisture. Some shady sites can be quite dry. Many plants will grow in the direction of the strongest light; one side of the plant will be thick and full while the other side will be sparse.

Tree shaded gardens become more shaded with time. As trees grow taller and wider they cast larger shadows and less light will penetrate the increasingly dense shade.The quickest way to admit more light is by removing lower tree limbs thus raising the height of the shade. This will decrease humidity and allow some filtered light to reach under-story plantings especially in the morning and afternoon. Some shrubs can be pruned into a tree form thus allowing more light to plants growing near their base.

Tree Roots
Trees differ in the number and depth of their roots. Maples, for example, have numerous shallow roots which makes digging, planting, or growing plants under them difficult. While tilling, creating raised beds, and root pruning are methods to cope with tree roots, these methods can lead to the decline or even death of the tree. The worst location for starting a raised bed is at the base of a tree; the additional soil can lead to decay organisms attacking the trunk or the main roots that support the tree. These methods are temporary at best since tree roots will grow into the newly amended soil or raised beds. In order to protect the tree, limit tilling and the addition of topsoil to a small percentage. Dig individual holes for shrubs and flowers instead of preparing beds. Filling in natural areas with compost, bark, and sandy loam for a raised bed is another option.

The following is a list of shrubs that will grow in partial shade: mahonia, rhododendron, azaleas, acuba, American boxwood, fatsia, gardenia, mountain laurel, pieris, camellia, cleyera, burning bush, hydrangea, anise tree, ligustrum, waxmyrtle, viburnum, and chaste tree. The following is a list of perennials the will grow in partial shade: irises, daylilies, balloon flower, astilbe, bee-balm, ageratum, black-eyed susan, bleeding heart, calla lily, columbine, and coral bells.

For more information about shade gardening call your local Extension Office at 919-496-3344. You can also visit our Facebook page.

If you have questions regarding any of the above topics, or any other questions you might have about gardening, feel free to call the Cooperative Extension Office at 919-496-3344.