Gardens Galore

Pruning Apple Trees

March 4, 2015

Pruning Apple Trees

Dr. Leonard Perry, Extension Professor
University of Vermont

Late winter is the best time to prune mature apple trees. If you’re buying young ones in the spring, they may or may not need pruning, depending on several considerations. Trees need to be pruned for best yields and longest tree life. How much to prune will depend on what type of tree you have.

Whether you have existing trees, or are buying new ones (remember when buying to get at least two different trees that are compatible for cross pollination), make sure you know the ultimate size. Dwarf (7 to 10 feet) and semi-dwarf (12 to 15 feet) may need less pruning than the traditional and now less common standard trees (more than 15 feet when mature).

The first branches to look for in pruning can be remembered by the 2 C’s and 3 D’s. Remove any that are crossing and rubbing on each other (keeping the most vigorous or branches pointed in the desired direction), and those that are crowded (this allows more light and air into the center of the tree, increasing growth and reducing diseases). Then look for pruning out any branches that are dead (discolored, no signs of buds, brittle), diseased, or damaged (such as broken by ice storms).

Trees should have well-spaced “scaffold” branches. These are the main branches that arise off the trunk, that help form the canopy, and from which lateral branches arise. These should be spaced up the trunk vertically 8 to 12 inches apart, 3 to 4 inches for dwarf trees. They should not arise off the trunk directly across from each other, nor directly above another branch.

The best branches are more horizontal than vertical. They’re stronger, less apt to break in wind and under fruit loads, and produce more fruit. So remove the more vertical ones. If many are vertical, you can use some tricks as growers do, either weighting them down slightly for the season, or place thin posts between branches to space them. Different cultivars (cultivated varieties) will have different growth habits. For instance, ‘Red Delicious’ tend to be more upright, ‘Jonagold’ and ‘Liberty’ tend to be more spreading.

Another term to know in pruning apples refers to the system. Most will be pruned to a “central leader.” As it indicates, this is simply leaving a main terminal shoot, and pruning off any on top near this that are competing to be the leader. It results in a cone-shaped tree like a Christmas tree shape. With such pruning, dwarf and semi-dwarf apples will be stronger and bear fruit sooner in their life. It also is good for weak trees, or those growing on poor soil.

If buying a young tree, it usually has already been pruned to set up this central leader habit. Look up the stem for the main upright leader coming off at a slight angle. This is where the original trunk was pruned back to an upward-facing bud, which now has grown into this stronger leader.

For established trees, if the leader grew over 18 inches the previous year (you can tell this by the lighter colored wood), prune off about one-quarter (cut off 4 to 5 inches of tip growth). Cut back to just above a bud, which will result in a new leader taking over, as described for young trees. More scaffold branches will grow too.

If the leader grew less than 18 inches last year, cut back both it and scaffold branches in order to stimulate more growth. Skipping cutting back the leader is fine if you want a more upright tree more quickly, or earlier fruiting on dwarf trees (but, at the expense of fewer branches and so less fruit overall).

A variation on the central-leader system is the modified-leader. With this system, once the tree is about 7 feet tall, cut back the top branches to about 6 feet. Then cut back similarly each spring. This results in a main trunk most the way up, which then branches into several scaffold branches, making the overall shape less conical but still upright. Use this for particularly vigorous trees, or to keep standard trees shorter (and so easier to manage).

Keep in mind that once a young tree has the correct shape and branch orientation, it will need little pruning compared to more mature trees— merely watch for the 2 C’s and 3 D’s, and pruning for shaping. Too much pruning of young trees will lead to excessive growth, and this will delay years to good fruiting. The more severe the pruning, the more growth the tree will produce. This may be desired if a tree is weak. But if a tree is vigorous, it’s better to cut back on fertility to reduce the growth rate.

A common mistake of beginning pruners is to cut off too much of last year’s growth, resulting in little to no fruit. Avoid pruning once the tree starts to leaf out, as this may interfere with flowering and so fruiting. Good times to prune in later winter are on days above freezing, not only as it is easier on the pruner but on the tree. Cuts made to frozen branches often result in injury and dieback.

Most apples produce fruit on “spurs”—short wrinkled stems less than 4-inches long that arise from branches. So it is important when pruning not to damage or break these off. Spurs usually don’t flower until the second year, and bear fruit starting the third year of their life. They may live for 10 or more years on apple trees.

Spurs occur on other fruit trees such as pears, but are most important on apples as there are specific “spur types”. These are strains of a cultivar, usually denoted as such as with ‘Crimson Spur Red Delicious’. A spur-type tree is generally about three-quarters the size of the regular cultivar, making them good for smaller spaces and properties. They tend to produce fewer and stronger limbs that are more vertical with more fruit. With fewer branches, these spur-types need less pruning.

On spur-types, if the branches have too many spurs (and so will produce too many fruit later that will need thinning out), snip some off. If there aren’t many spurs on a spur-type tree, “head back” the branches to produce more. This is simply shortening branches or pruning them back part way.

For most mature trees, particularly if not spur types, don’t head back long branches. Remove them at the trunk instead to avoid promoting excessive inner shoots called “water sprouts”. If your tree has such a clump of shoots arising from a branch, often from just below a pruning cut, remove them. When cutting a branch back to the trunk, don’t cut into the ridge of bark (the “branch collar”) from which it arises. Nor do you want to leave a stub. Cuts made “flush” with the outermost collar will heal the fastest.

Remove any shoots called “suckers” arising from the base of the tree. Most trees are “grafted”, with the desired variety growing out of a vigorous rootstock of a different variety. Many suckers arise from below where these two join—the graft union. They take energy from the tops, and may lead to a whole different variety that isn’t desired. Often they form in response to some injury or weak growth on the top of the tree, so consider if this might be the cause.

More tips on pruning apples, diagrams, and tips on pruning other fruit trees can be found in the Fruit Gardener’s Bible by Lewis Hill and Leonard Perry. More information on this book, and other fruit growing resources, can be found online at homefruitgrowing.info.

3/1/15

Distribution of this release is made possible by University of Vermont Extension and New England Grows–a conference providing education for industry professionals and support for Extension’s outreach efforts in horticulture.

Garden Trends for 2015

January 26, 2015

Dr. Leonard Perry, Extension Professor
University of Vermont

Health, nature, and living outdoors are some of the key gardening trends nationwide for this coming year. Each year, the Garden Media Group (www.gardenmediagroup.com)– a marketing firm for the home and garden industry—identifies key trends for the coming season. For 2015 they’ve pegged nine of these, which you’ll no doubt see reflected in products, plants, and advertisements. These relate to a desire in many consumers to “increase their overall well-being, lead a sustainable lifestyle and make a positive impact on their communities and the planet.”

New consumers. More new gardeners will come from the Millennials (those that follow Gen Xers, roughly those born in the 1980’s and 1990’s), Hispanics, and Young Men categories. Millennials are a larger group than the Baby Boomers, comprising about 1/4 of the U.S. population, and spend about four times more on gardening than the national average. Young Men also spend more than average. Hispanics have a big interest in growing vegetables, which will drive this trend nationwide.

Health. According to the trends report, health is a concern not just for individuals. “People aren’t just gardening for beauty, they are gardening to nourish their communities, the environment, and their own well-being.” Edible plants, such as berries, will remain strong. Included in popular products will be those environmentally friendly and safe for pets and children. People will be concerned with the effect of products on birds and bees. Plants will be seen as good for cleansing air, making oxygen, and overall wellness. More will learn that trees absorb 1/5 of carbon emissions, reduce electricity consumption, and increase mental health.

Color. Look for “pops of exploding color like pink and teal”. Bubblegum petunia in turquoise planters are an example. Other popular colors should include rustic, natural palettes, light pastels, and worn-in hues such as denim.

Garden-tainment. This means “the party is moving outside” as people enhance outdoor living spaces and personalize them, using them as an extension of indoor living spaces. Look for ready-to-go plants for instant effect in such spaces, grilling and cooking outdoors, and all manner of containers. The majority of younger consumers (Millenials and GenX) rated such outdoor rooms as important or very important.

Compact yet bold. Compact plants and containers with bold plants to make a quick statement will be popular. Larger decorative containers will be seen more. Tiny succulents, being attractive and easy to grow, will remain popular.

Portable gardening. This caters to an increasingly mobile audience. The word “NOwners” has been coined to refer to “those who prize freedom over home ownership” (or perhaps just rent or can’t afford to own a home). Look for more lightweight and adaptable planters with wheels, handles, and moving parts that make them both decorative and mobile.

Neighborhood rebels. You probably won’t see this trend as much in rural areas, as it refers to residents of neighborhoods and planned communities rebelling against ordinances that limit their freedom. It’s estimated that over 63 millions Americans lived in over 323,000 such urban communities. These folks are transforming neighborhoods into “agri-hoods” with urban chickens, bee keeping, clotheslines, food gardens, and landscapes without lawns.

Garden naturally. Increasingly you may see this landscape style which could be termed “anything goes”. It is a casual style, of really no formal style, inspired by the natural landscape. Look for more “meadows and natural habitats using native plants to increase diversity, balance, and ecosystems.” Being adapted to local climates, native plants need less water and fertilizer and pampering, and support healthier ecosystems (like bugs for birds to eat—a main part of their diet).

Smoke your garden. This last trend relates to almost half the states passing laws legalizing marijuana. The trend group expects more people will begin growing their own. While you may not see plants and seeds just yet in stores, you may see more growing lights and supplies—all useful for growing your own seedlings and houseplants indoors too.

01/1/15

Looking for Mites and Other January Gardening Tips

January 9, 2015

Leonard Perry, UVM Extension Horticulturist
and Charlie Nardozzi, Horticulturist

Checking houseplants for spider mites and other insects, cleaning bird feeders, and disinfecting seed starting containers are some of the gardening activities for this month.

Aphids and spider mites may be multiplying like crazy amidst your houseplants, especially if they are grouped close together. Isolate each plant and inspect it closely with a magnifying glass if necessary. Aphids are easier to see, come in many colors, and move about on new growth and stems in particular. Look under leaves and where leaves join stems for the characteristic webbing of spider mites. Palms and English ivy are favorites of spider mites.

Treat these pests by holding the plant and pot upside down and submerging the foliage in a sink full of soapy water (wrap aluminum foil over the soil to keep it from falling out). Use a mild detergent, or weak solution, so not to damage the plant leaf surfaces. In severe cases, spray the plant with insecticidal soap or similar insecticide for indoors.

Birds deserve clean food surfaces as much as we do. Every few weeks bring the feeders inside and wash them with soap and water into which a little bleach has been added (one part bleach to nine parts water). Rinse thoroughly and dry.

If you have a heated bird bath (a good idea if you don’t), make sure to clean it every few days too. I have an old brush just for this purpose. Don’t use your kitchen one that is used on eating surfaces. Of course these can just be cleaned outdoors when filling them.

Take inventory of trays, pots, and six-packs from past years and discard any that are cracked. To get off to a clean start with seed starting this year, disinfect flats and pots in soapy water with bleach added: one part bleach to nine parts water. The longer you can soak them, the better, but at least try for 10 minutes. Then rinse well. Be sure to scrub off any soil before this cleansing rinse. If you prefer not to use bleach due to its chlorine fumes and caustic nature, a household disinfectant (such as the Lysol brand) can be used instead, with one part of it to two parts water.

If that geranium or coleus you’re overwintering inside has sent out spindly new shoots, keep trimming it back until the increased sunlight can support sturdier growth. If you have low light, keeping the plant in a cooler location (50 to 60 degrees F) may help.

Orchids are one of the most popular flowering potted plants now, and a common one often found in garden stores and retail chain stores is the moth orchid (Phalaenopsis). When in flower, they need consistent temperatures of above 60 degrees at night and above 70 during the day. In New England, a south window in winter is not too much light, whereas it would be too much in summer.

Fertilize orchids with a dilute liquid orchid fertilizer (high phosphorous, low nitrogen). Let the soil dry out somewhat between waterings but not get completely dry. The flowers can be damaged by gas from a stove, cigarette smoke, and other chemicals in the air. If buds drop before opening, raise the humidity with a room humidifier or by grouping plants together on top of pebbles in a tray with water up to the bottom of the pebbles.

Other gardening activities for this month include keeping bird feeders filled daily or as needed, checking stored summer bulbs (like dahlias) and root crops (like winter squash) for rots, and studying seed catalogs and online websites for new varieties for this year’s garden.

01/1/15

Charlie Nardozzi is a nationally known horticulturist, author, gardening consultant, and garden coach (CharlieNardozzi.com). Distribution of this release is made possible by New England Grows– a conference providing education for industry professionals and support for Extension’s outreach efforts in horticulture.

Fun Facts About Poinsettias

December 6, 2014

Dr. Leonard Perry, Extension Professor
University of Vermont

Do you like trivia, or at least learning more about the top-selling holiday plant? If so, perhaps you will be interested in a dozen fun facts about the poinsettia plants you buy and see everywhere each December.

Fact 1: Did you know that the poinsettia’s main attraction is not its flowers, but its leaves? The flowers of the plant are the yellow clustered buds in the center (termed “cyathia”). The colored leafy parts are actually bracts or modified leaves, that turn color in response to the plant forming flowers. When buying a poinsettia, make sure it has the buds, preferably not yet open.

Fact 2. Red is the most popular color, accounting for roughly three-quarters of all sales nationwide, followed by white and pink. The more than 100 varieties of poinsettias come in a range of colors from red, salmon, and apricot to yellow, cream, and white (but not blue—these are a designer color created with dyes). There are also unusual speckled or marbled varieties with several colors blended together. New varieties are introduced yearly.

Fact 3. How many poinsettias do you think are sold in a year? According to the 2014 USDA Floriculture Crops report, poinsettias accounted for about one-fifth (19 percent) of sales of all flowering potted plants. In economic terms, that’s $146 million out of a total of $778 million in sales of all flowering potted plants, with about 35 million pots sold. This makes them the highest selling potted flowering plant.

Fact 4. Although every state in the United States grows poinsettias commercially, California is the top producer with almost 7 million pots grown, followed by North Carolina with 4.3 million pots sold, Texas with 3.3 million, Florida with 3.2 million, and Ohio with 2.9 million poinsettias sold.

Fact 5. Did you know that in the wild, or planted in tropical climates, the poinsettia can reach heights of 12 feet with leaves measuring six to eight inches across? It is actually a small tropical tree (Euphorbia pulcherrima) belonging to the Euphorbia plant family.

Fact 6. A native of southern Mexico, the poinsettia blooms in December and has been used in that country to decorate churches for centuries. In the fourteenth to sixteenth centuries, the Aztecs used the poinsettia leaves to dye fabric for clothing and the sap for medicinal purposes, including to help control fevers. They also considered the red color a symbol of purity, and so poinsettias were traditionally part of religious ceremonies. In Mexico and Guatemala, the poinsettia is called (translated) the “Flower of the Holy Night” referring to Christmas Eve.

Fact 7. Dr. Joel Roberts Poinsett, an amateur botanist and first United States Minister (the position called “ambassador” after 1896) to Mexico, introduced the plant that became known as the poinsettia to this country. He discovered a shrub with brilliantly colored red leaves growing by the side of the road in Taxco, Mexico, in December 1828 and sent cuttings home to his plantation in Greenville, South Carolina.
Most botanists at that time dismissed the poinsettia as a weed. Fortunately, Poinsett continued to study and breed this plant in his greenhouse, sharing plants with his horticulturist friends. It soon gained acceptance as a holiday plant, despite its very short bloom time. It wasn’t until the 1960s that researchers were able to successfully breed plants to bloom more than just a few days.

Fact 8. Here’s another bit of interesting trivia. December 12 is National Poinsettia Day (www.poinsettiaday.com/). Never heard of it? Believe it or not, the United States has observed this official day since the mid-1800s. It honors the man and the plant he introduced. Poinsett died on Dec.12, 1851.

Fact 9. For much of the last century, the Paul Ecke Ranch in Southern California produced the majority of poinsettia cuttings and plants purchased in the U.S. and many of those worldwide. Paul Ecke, Jr. is considered the father of this industry, as it is he who figured out a method for getting poinsettias to branch. Prior, they grew tall so stems had to be bent back into a loop, or “tromboned,” to keep them at a desirable height. It is from this plant and firm that the football bowl game in San Diego gets its name.

Fact 10. True or False. The poinsettia is a poisonous plant. If you answered false, you’re correct. The plant has been tested repeatedly and cleared of this charge by authorities such as the National Poison Center in Atlanta, Georgia, and the American Medical Association. However, this doesn’t mean that poinsettias are meant to be eaten. If ingested, this plant can cause stomach irritation and discomfort. Cats and children also may choke on the fibrous parts, so be sure to keep these plants out of their reach. The sticky white sap also may cause skin irritation for some people.

Fact 11. Do you know the best way to prolong the life of this Christmas plant? Avoid hot or cold drafts, keep the soil moist not soggy, and place in a room with sufficient natural light and temperatures of around 60 to 70 degrees F. Water when the soil begins to dry. Once the leaves wilt too far, it’s too late.
Above all, protect it from exposure to wind or cold on the way home from the store. Poinsettias are highly sensitive to cold temperatures and even a few minutes of exposure to 50-degrees F or lower temperatures will cause them to wilt. But when cared for properly, poinsettias usually will outlast your desire to keep them!

Fact 12. The most common question many have is, can I get the poinsettia to rebloom next year, and if so, how? Yes is the short answer, but it requires some work and regularity. If you want to try though, keep in mind that flowering in this plant responds to short daylengths (or actually long nights). They need daylight for no more than 10 hours daily, beginning around October 1. So you’ll need to place plants in a darkened closet or room (with no lights at any time) from about 5pm to 7am or so, daily, for 8 to 10 weeks. Don’t forget to bring it back into the daylight every day! Even if you are successful, keep in mind that much superior plants will be available from greenhouses and growers, as well as new varieties in all sizes.

12/1/14

Winter Squash

November 30, 2014

Dr. Leonard Perry,
Extension Professor University of Vermont

Versatile, variety, and nutritious are all adjectives that can be used for winter squash. Whether you grew your own, or buy them from local farmers and markets, consider putting some up for winter. With proper storage of squash, you’ll benefit from their fresh flavors for months—often until next spring– as well as the nutrition of these vegetables.

Although winter squash has the same calories roughly as potatoes, it has more than twice the potassium. Winter squash provides various vitamins such as A, B6 and C, fiber, and minerals that may reduce the risk of certain cancers. These squash are a good source of anti-inflammatory nutrients needed for a strong immune system, such as omega 3’s and beta-carotene.

Winter squash store well, such as in a cool room or basement, which stays around 50 to 55 degrees (F). Acorn squash can store 3 to 4 months, other winter squashes can last up to 6 months or more.

So just what are winter squash, and all the types you may find? They’re one of the two major group of squashes, the other being summer squashes like yellow and zucchini. They’re so named as they’re harvested later—early fall around the time of first frost—and last well into and through winter. They’re one of the few vegetables native to North America, and have been grown as one of the “three sisters” by native peoples along with corn and beans.

Squashes are in the cucurbit family, related to cucumbers, melons, and gourds. Among the three main winter squash species, there are at least a dozen main types you may find.

Acorn are one of the most common winter squashes, medium size with an acorn shape, ridges, and dull green rind. Acorn squashes that have turned orange will have tough and fibrous flesh inside. It has a mild flavor, good for soups, baking, and stuffing.

Buttercup is similar in size to the acorn, only more squat with smooth dark green rind with some pale streaking. Some varieties may have a small bump on top, as it is a type of “turban” squash (see below). Its distinctive circular ridge on the bottom sets it apart from the similar “kabocha” squash (see below). Cooked, its flesh is mild and somewhat dry.

Butternut is another of the more commonly seen and used winter squashes, having a distinctive elongated pear shape—long neck and bulbous base– with tan rind. The flesh has a sweet and nutty flavor, and is bright yellow-orange. Similar to the acorn, roast it, mash it, or make into soup. It’s easier to deal with cutting the neck from the base, and handling each separately. To remove the hard rind, use a vegetable peeler once it is roasted.

Carnival squash is a cross between Sweet Dumpling (see below) and acorn squashes, and is similar in size and shape. It is light in color, white and yellow, with ridges. Use it similar to acorn or butternut squash.

Delicata is often called a “sweet potato squash” as it has a similar consistency when cooked, and similarly is sweet but more “earthy”. It is small, oblong, and pale yellow with green stripes. The thin skin makes it easily bruised, but also makes it edible. Use as you would a sweet potato, or simply cut in half, scoop out the seeds, and roast with olive oil and salt.

Hubbard is one of the larger squashes, noted for its size, teardrop shape, blue-gray rind and bumpy surface. It is good roasted, and sometimes is used as a vegetarian turkey substitute at Thanksgiving. The flesh has a pumpkin flavor.

Kabocha is a Japanese type of winter squash (this being the generic name for squash in Japanese), similar to the buttercup in appearance and coming in green or red. The deep yellow flesh is flaky but sweet, good roasted or baked with plenty of butter or oil.

Pumpkins are well-known, and come in sizes from tiny decorative ones to the giant ones you see at fairs and competitions. Keep in mind the ones for carving generally lack flavor, while the Sugar Pie ones have the sweet, pumpkin flavor good in pies, soups, or roasted. The squat and colorful French heirlooms are both sweet and ornamental.

Red Kuri is another Japanese squash, similar to a small Hubbard only with a red-orange rind and so is sometimes called a red Hubbard. The yellow flesh has a flavor resembling chestnuts, and is good roasted or the squash split and stuffed.

Spaghetti squash is light yellow, large, and oblong. Once the flesh is cooked, run a fork through it to make long “strings” that resemble spaghetti. In fact it makes a healthy alternative to pasta, with a mild flavor. This, as well as the Acorn and Delicata are very closely related to the summer squashes, just different varieties of the same species.

Sweet Dumpling is one of the parents of Carnival squash, being compact, whitish-yellow with some green streaks, and pronounced ridges. Its taste resembles a sweet potato, and its flesh is edible. This could be used in place of sweet potato or pumpkin in recipes.

Turban is the larger group of which Buttercup is a member, noted for its pronounced “bump” on top resembling a turban or turk’s cap—another name for it. Often these are quite colorful and can be used simply for decoration. Its sweet and mild flesh is good roasted, or in soup, and its outer rind can be used as the soup tureen.

There are many more types and cultivars of winter squash, including heirlooms. Experiment with some in this winter’s cooking, and try growing some from seeds next year.

11/1/14 Distribution of this release is made possible by University of Vermont Extension and New England Grows–a conference providing education for industry professionals and support for Extension’s outreach efforts in horticulture.

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