By Richard Shiell Few trees match the spectacular spring show of a flowering crab blossoming abundantly in pink or white. In early summer, the trees are lush and attractive as hundreds of colorful little fruits develop among the glossy green foliage. Unfortunately, with many of the older varieties, however, ugly brown blotches of apple scab appear as summer wanes, and the leaves start to drop off. By late summer, the trees are nearly bare. The crabapples fall to the ground and rot, or kids in the neighborhood throw them at passing cars. That's not the case with the newer varieties. Plant breeders have introduced hundreds of new varieties in the past two decades, many of which are naturally shapely and very ornamental all year-round. The greatest improvement is in the persistence and color of the fruits. These diminutive apples range from glossy red to orange, burgundy or even yellow. In many cultivars they hang on the branches all winter, providing a bright spot in the winter landscape as well as food for wildlife. And with improved disease resistance, many cultivars retain their foliage into the fall. With hundreds of good varieties available, shopping for a flowering crab can be a little overwhelming. Growth habits can range from rounded to weeping or even columnar, depending on the variety. When choosing a cultivar, first consider its size and shape at maturity and confirm its disease resistance in your area. Next, choose the color of fruit your prefer -- the fruits last much longer than the flowers and are ornamental during the season when little else is. Then consider the foliage, as some cultivars have purplish leaves or develop good fall color. All crabapples have beautiful flowers; the white-flowering varietes generally have more brilliantly colored fruit than the "rosybloom" crabs. Old varieties with severe disease problems are still common in the nursery trade. Among the common scab-susceptible varieties are: Hopa, Eleyi, Red Silver, Flame, Radiant, Evelyn, Sparkler and Vanguard. These cultivars grow well in dry-summer areas like the Rocky Mountains, but in the East or Midwest they may require six or eight sprays annually. Should you already have a susceptible tree, the best way to prevent apple scab is to clear the ground beneath the tree every year late in autumn. Remove all fallen leaves, twigs and fruit debris, as these carry the overwintering fungus, which produces spores in spring and infects new foliage. And seriously consider replacing the tree with something better. Crabapples grow quickly, and you will be much happier with with one that never requires spraying to stay healthy and attractive. A less problematic disease that almost all crabapples are susceptible to is fire blight, a highly weather-dependent bacterium (Erwinia amylovora) transmitted at blooming time by blowing rain, wind and bees. It causes entire branches to wither as if burned (hence the name). Few crabapples have good resistance to fire blight, but Prarifire, Professor Sprenger and Profusion are more likely to remain healthy in areas where the disese is widespread.. A few crabapples are affected by cedar apple rust. This disease requires an alternate host: There must be an eastern red cedar (Juniperus virginiana), Rocky Mountain juniper (J. scopulorum) or creeping cedar (J. hortizontalis) within a few hundred feet of the crabapple for the fungus to complete its life cycle. An infected crabapple will develop leaf blotches with wide yellow edges and gradually defoliate. Fortunately, most hybrid crabapple varieties are resistant. If you have seen the bright orange spore-producing bodies of the cedar apple rust fungus growing in spring in cedars near your garden, avoid planting susceptible crabapples such as Brandywine, Bechtel, or Malus ioensis 'Klehm's'. Autumn is a good time to view potential specimens -- the leaves are gone and you can see the tree's branching structure. The fruit color is also at its peak then, too. Late fall is a good time to plant as well; sometimes trees dug just before blooming never leaf out well, and take years to recover. If you do plant in spring, remove all developing fruit right after bloom so the tree can concnetrate on developing a root system. Cream of the Crop Crabs As a landscape architect, I frequently include the following varieties in my residential designs: Prarifire, Red Splendor, Profusion, Donald Wyman, Red Barron, Harvest Gold and Red Jewel. I've noted unique or noteworthy characteristics of these favorites, along with 10 others, in the following list of cultivars that I consider to be some of the best. White-Flowering Crabapples (exceeding 15 feet in height) Donald Wyman. The favorite crabapple of many growers, Donald Wyman is particularly shapely, reaching up to 20 feet in height with a broad canopy. The small red fruit remain throughout winter, and are not taken by birds. Donald Wyman resists most diseases but may have problems with mildew if not grown in full sun. Harvest Gold. Its name derives from the amber yellow fruit, which colors up later than other crabapples, darkening to cider brown when winter temperatures drop below freezing. Apple scab can infect it, but resists defoliation. M. sieboldii var. zumi 'Calocarpa'. This upright-branching tree, aptly called the redbud crab, bears a heavy crop of moderately fragrant flowers and tiny bright red fruits that persist into December. The dense foliage turns yellowish in fall. Professor Sprenger. An exceptional tree developed in the Hague in Holland by the past Director of the Parks Department, S.G.A. Doorenbos (who also developed Liset and Profusion). Noteworthy for its unusual orange fruit color, and for extreme disease resistance. The blossoms are particularly fragrant. The fruit remains throughout winter. Rosybloom Crabapples (exceeding 15 ft. in height) Indian Magic. A popular and widely available medium-sized cultivar that fits well into the home garden. The branching tends to be even and symmetrical, and the relatively small leaves go well with fine-textured companion plants. Susceptibility to scab is about average, but scab-infected leaves fall off early without turning brown, so the tree maintains a neat appearance. During the fall, the leaves turn bright yellow. The abundant reddish or orange-toned fruit develop color early. Freezing temperatures soften the hard little fruits enough to make them edible for wildlife, so Indian Magic is particularly good as a food source for overwintering birds. Makamik. Introduced in 1933 by the Canadian Department of Agriculture in Ontario, this very hardy cultivar is widely planted in Canada, but is uncommon in the United States. In my experience its large pink blossoms are the most fragrant of any crabapple tree. The glossy deep green foliage is very scab resistant. The fruits, which are fairly large, begin to shrivel up after the first hard frost, but remain on the tree, giving it a very rustic appearance during winter. This 20' to 25' tree makes a good background specimen in large garden areas. M. floribunda. The common name for this species is the Japanese flowering crab. The buds and newly opened flowers are deep rose pink. Each petal fades from the center out, leaving a rich band of color around a pink center. Prarifire. Developed by Dr. Dan Dayton, a plant pathologist at the University of Illinois, Prarifire is widely considered one of the best rosybloom crabapples. Exceptional disease resistance makes it suitable for areas of the country where high humidity encourages fungal diseases, or where fire blight commonly occurs. The conical maroon fruits last well into winter. The bark is an attractive dark red-brown. Profusion. Since 1946 this tree has enjoyed wide popularity for its good color and relatively fast growth rate. The branching habit is quite upright, lending itself well to planting beside buildings. The color of the blossoms fades gradually, so a specimen in full bloom contains a range of colors from dark rose pink to pale pink. Abundant maroon fruits cover the branches throughout winter. Profusion can develop scab in wet years, but does not defoliate. Red Splendor. Introduced in 1948 in Fertile, Minnesota, this variety is widely available in zones 3 to 5 (it should also do well in zones 6 and 7). It has fairly good disease resistance. The bright red fruits stay on the tree until spring. This variety tends to produce many water-sprouts, so it requires trimming annually. Other Crabapples (compact, weeping, columnar and edible) Coralburst. A slow-growing shrub crabapple often grafted onto a standard to increase its height. The red buds open into unusual double pink flowers. The sparse yellowish fruit fall off soon after freezing. David. This is one of the most disease-resistant cultivars. Unfortunately, some specimens only fruit heavily on alternate years. The fruits darken to deep red after freezing and stay on the tree for months. In mild climates David can lose some hardiness, and freeze back in the occasional bad winter. A good bird-feeding tree when the fruit soften in spring. M. sargentii. A dwarf crabapple grown either as a multi- trunked shrub or as a small tree, the Sargent crabapple works especially well at the edge of a large lawn or low planting with larger trees behind it. A good birdfood source, but it tends to have few fruit on alternate years. Recommended wherever summer humidity is high because of its excellent disease resistance. Ralph Shay. Named after a plant pathologist at Purdue University, this cultivar is a cross between the crabapple zumi 'Calocarpa' and a true apple, 'Wolf River 1881', which produces gigantic fruits weighing nearly a pound each. The offspring of this odd match is a disease-resistant tree that bears unusual red fruits with pointed bottoms and a tart flavor. They remain on the tree for several months. Recommended for cooking. Red Barron. Few rosybloom crabapples grow into an upright or columar shape, and this is about the best of them, even though it is susceptible to scab. Red Barron is also noteworthy for its fall color, with tones of purple, red and orange. Red Jade. The most widely planted weeping crabapple, and a truly exceptional plant for bird lovers. Cedar waxwings and other birds converge on Red Jade in late fall to gorge themselves. Unfortunately, this slow-growing variety is not very disease resistant, so it tends to lose some foliage to apple scab in wet years and should not be planted in areas where fire blight is common. Red Jewel. This is one of the best crabapples for winter interest, producing abundant small red fruits so hard birds don't eat them. Hardy to zone 5a, it has suffered die-back problems in Minnesota. Easy-Going Crabs Crabapple trees don't require much special care or maintenance. They are amazingly tolerant of soil conditions (but alkali clay will slow their growth). Full sun and infrequent deep watering are recommended. A single application of a time-release fertilizer in spring is all the feeding required, unless the soil is too low in organic matter [then amend with what, and how much]. Avoid overfeeding, which encourages soft, unshapely growth. Pruning requirements vary among types of trees; few are naturally shapely, most should be thinned every year or two. Many varieties are prone to producing water-sprouts (vertical branches in the middle of the canopy), which should be removed. Landscape architect Richard Shiell has designed, photographed, and written about gardens from California to Ohio to Minnesota. He currently resides in Bakersfield, California.
Provided by NGA
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