Ask a Master Gardener: Restoring fruit trees
Dear Master Gardener: In our yard we have an old apple tree that is a mess of tangles and dead branches. It produces only a few apples every other year but we like the way they taste. What can I do to restore it to health?
Answer: This sounds like a situation calling for pruning. Pruning is essential for reliable fruit production on apple trees. It also spaces out the fruit, allows sunlight to reach the fruit, increases air flow and focuses the tree’s energy on producing bigger and tastier apples. It should be done every year. Your goal should be to have a tree with a strong central leader with evenly spaced side branches, wide at the bottom, narrower at the top. That is easier to accomplish with young trees, difficult, if not impossible, with older trees such as yours.
Start by arming yourself with good, sharp pruning tools, ideally a lopper and a pruning saw. Begin with branch removal. The DDDC formula for dead, diseased, damaged and crossovers, can be helpful. A dead branch cannot be restored, so remove it, all the way to its branch collar (the circular swelling where the branch meets its main limb). Diseased and damaged branches should be removed back to healthy wood. Crossovers are branches that rub against one another, or soon will, inviting insects and disease. Avoid topping or shearing the leader, which promotes excessive vegetative growth and produces poorer apples. Each year you will find new “water sprouts”, fast-growing branches growing straight up — remove all of them. From this point on, further pruning decisions are judgment calls. Such things as proximity to buildings, lawn-mowing height and hazard situations will influence your decisions. Finally, remove ALL suckers, the vertical growth at ground level. You do not need to “paint” any cuts with wound dressing.
The best time to prune is late winter or early spring, while the tree is still dormant, usually late March or early April here in Crow Wing County. Prune early and do not be afraid to prune a lot. Many, if not most, apple trees produce a sizable crop only every other year. Pruning often induces heavier crops in the “off” years.
■ Dear Master Gardener: I have found some insects in my basement that I think are either millipedes or centipedes. Can they harm clothes or furniture? How can I get rid of them?
Answer: Millipedes and centipedes are arthropods related to insects. When found outdoors, typically under decaying leaf litter or other organic matter, they are considered beneficial. On the other hand, finding them in your home can be unnerving. Rest assured they are not harmful to food, clothes, furniture, or other items found in your home. They are usually found in basements and can enter your home through cracks in the foundation, around ground-level windows and under doors. Millipedes can be found indoors in early spring as they emerge from cracks and crevices where they spent the winter. Centipedes can sometimes be found in homes too but usually when the weather is warm. A millipede is a 1-1 ½ inch, dark brown, worm-like creature with up to 400 very short legs. They are mostly active at night, usually hide under objects where it is dark and damp, and curl up tightly when touched or after it dies. House centipedes are more than one inch long, brownish or grayish-yellow, with a flattened body containing 15 pairs of long jointed legs attached along the sides. They also have a pair of long feelers, which extend from the head. You may see quick-moving centipedes running across a wall, ceiling or open room toward a dark area. Like millipedes, centipedes are also associated with damp conditions.
If possible, tolerate these beneficial arthropods and use insecticides as a last resort. Insecticides are unnecessary for controlling millipedes as they often die soon after entering homes because it is too dry. Centipedes are beneficial because they eat small insects, spiders and other arthropods. You can take some steps to reduce their numbers by caulking or sealing cracks and other openings in exterior foundation walls, around doors and ground-level windows by late summer. Remove leaf litter and decaying vegetation from around your foundation and thin foundation plantings to allow the soil to dry more quickly near the foundation. If millipedes are found alive inside a home, it is usually an indication of excessive moisture present; therefore a long term solution is necessary to dry the room (for example, a dehumidifier). Kill and remove centipedes and vacuum up millipedes as you see them. You can also set out sticky traps (for example, Roach Motel) on floors to catch centipedes in the area where you see them. Remove any unnecessary boxes, bags, or clutter that gives centipedes favorable places to hide. Caulk or seal behind baseboards and in cracks and crevices where centipedes like to hide.
■ Dear Master Gardener: I would like to make a dish garden with a southwestern theme and was wondering what plants would fit the bill.
Answer: Succulents are great plants for a dish garden. Succulents refer to a broad category of plants, which include cacti. They have thick fleshy leaves or stems, which serve as water storage organs to ensure survival under very dry conditions. In addition to cacti, some other succulents you may want to consider are: jade plant (Crassula arborescens), snake plant (Sansevieria trifasciata), medicine plant (Aloe barbadensis), century plant (Agave americana), Kalanchoes (Kalanchoe blossfeldiana), sedums (Sedum sp.), and hens and chicks (Sempervivum sp.). These plants do very well as houseplants because the relative humidity in most homes is usually low. Mix one part potting soil with one part coarse sand and sterilize. You can sterilize potting medium by moistening the soil mixture, covering it with aluminum foil to keep it from drying out while being heated, and place it in a 200° oven for about 30 minutes. Succulents require a bright sunny window.
When you group succulents and cacti together in a dish garden, choose plants that have a similar growth rate and similar water requirements. Since dish gardens rarely have drainage holes, it is important that you do not over-water the plants. Even if you have some pebbles at the bottom of the container to allow some drainage, any excess moisture will be drawn back into the soil and keep the roots moist for too long, possibly causing fungal or bacterial rots.
■ March garden tips:
• If we have a March thaw this year, bulbs that emerge will survive, but flowers will most likely be lost for this year. Next fall mulch the bulbs more heavily or move them to a location less susceptible to fluctuating temperatures.
• March is a good time to propagate houseplants. For most plants take a 4-6 inch cutting with a sharp knife and remove the bottom 1-2 leaves, which is where most roots will form. Dip the cut end in rooting hormone and place it in moist soilless potting mixture. Keep well watered until a gentle pull indicates that roots are taking hold. Then repot in a more nutrient-rich soil and resume normal care.
• If you haven’t had your soil tested in the last 5 years, do so as soon as the soil thaws. For a University of Minnesota test, Google “soil test UMN” for instructions. The current cost is $17.00.
• If snow mold has been a problem in previous springs, stay off the lawn as much as possible until snow and ice melt. Then use a leaf rake on thawed soil to fluff up the grass and thereby increase air circulation to prevent mold.
• Vegetables that can be started this month in a bright sunny window or under grow lights: parsley, broccoli, early cabbage, cauliflower, celery ad eggplant.
• Annuals that can be started now: Coleus, Dusty Miller, Pinks, Snapdragon, Verbena, Alyssum, Moss Rose and Salvia.
• Repot stored geraniums. Cut them back to 4-6 inches above the container and restart a watering, feeding and sunning program.
Crow Wing County Master Gardeners are trained and certified volunteers for the University of Minnesota Extension Service. All information given in this column is based on research and information provided by the university. To ask a question, call the Master Gardener Help Line at 218-824-1000, extension 4040, and leave a recorded message. A Master Gardener will return your call.