Important Gardening Interview Preparation Guide

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What you describe is a typical symptom of Verticillium wilt, a soil-borne fungal disease that affects the vascular systems of Japanese, Norway, silver, and sugar maples, as well as many other plants. Leaves will often turn yellow or brown and entire branches will die. In Diseases and Pests of Ornamental Plants, author Pascal P. Pirone states that in the early stages of the disease wilt symptoms are usually confined to single branches or to one side of the tree. Small plants or trees may die within a single season, but larger, mature trees may live for many years, or even recover from the disease under optimal conditions. Trees showing widespread and severe infection are unlikely to be saved. In cases where only a few branches are affected, the tree may be helped by regular watering and the application of a slow-release fertilizer around the base of the tree early in the growing season. Regular applications of fertilizer stimulate rapid growth and may result in the formation of a thick layer of sapwood that seals off the infected tissue. Diseased branches should be cut off well below the affected section and destroyed. Plants that are susceptible to Verticillium wilt should not be planted in soils known to be infected with the fungal disease.

Earwigs are omnivorous—they eat plants, other insects, and decaying organic matter—but the damage they cause to garden plants is usually negligible. In fact, they are predators and often help control populations of far more destructive plant feeders such as aphids, nematodes, and mites. Night-feeding earwigs are sometimes blamed for injury that other pests have caused, because they like to hide in damaged plant tissues during the day. There’s no reason to control earwigs unless you are sure they are responsible for unacceptable plant damage. In that case, you can keep them in check with insecticidal soap, which is available in most garden centers and hardware stores.

The most commonly grown strelitzia is Strelitzia reginae, commonly called bird-of-paradise. It produces brilliant, birdlike orange and purple flowers on top of long stalks of glossy greenish-blue foliage. These subtropical plants need a rich, well-drained soil containing a lot of organic matter. Place them in a brightly lit spot with temperatures of about 68 to 75 degrees during the day and night temperatures about 10 degrees cooler. During the growing season, allow the soil to dry out slightly and then water them well. Feed them with a dilute liquid fertilizer every two weeks. The plants like their foliage misted daily and year-round humidity levels of about 35 percent.

In the winter, the plants need a resting period. Keep them at about 55 degrees, decrease watering, and stop fertilizing.

Plants need to be potbound before they will flower, so don’t transplant them to a larger pot until the roots have filled up more than three-quarters of the soil area. Plants grown from seed take seven to eight years to flower. Those propagated by division take about four years.

Moses-in-the-cradle (Tradescantia spathacea; formerly Rhoeo spathacea), also called boat lily and numerous other common names, is a member of the spiderwort family. It is prized for its dark metallic green leaves that have glossy purple undersides. Small white flowers are borne within purple, boat-shaped bracts (the cradle) that are formed in leaf axils. Indoor Plants, by George B. Briggs and Clyde L. Calvin, suggests that the plants need full sun and moderate humidity, temperature, and water. The plant does not require pruning but should be fertilized four to five times per year from April to August.

All plants give off plenty of oxygen, and some help to remove pollutants from the air. While no plant will grow without any light, there are many that can be grown under fluorescent lights. Unfortunately, few flowering plants will grow or thrive under standard artificial lighting, so unless you purchase and install professional-quality grow lights, you’ll have to stick to foliage plants. Some plants that do well in low-light situations include: spider plant (Chlorophytum spp.), cast-iron plant (Aspidistra elatior), golden pothos (Epipremnum aureum), kangaroo vine (Cissus antarctica), grape ivy vine (Cissus rhombifolia), spotted evergreen plant (Aglaonema costatum), Chinese evergreen (Aglaonema commutatum), and snake plant (Sansevieria spp.). Many of these common indoor house plants can be purchased at your local garden center or greenhouse.

Don’t worry about the leaf drop. It’s natural for a hibiscus to drop leaves when it is brought into dry indoor air. Mist it often to help it adjust. It will overwinter well as long as it isn’t over-watered. This may be happening if the foliage turns from strong green to a ghostly green. If that occurs, take it out of the pot and let the root ball dry for a day or two before you put it back. Fertilize with a dilute, balanced mix once a month until the days begin to lengthen and new growth begins.

In order to propagate the gardenia, use greenwood and semi-ripe cuttings taken as nodal stem-tip cuttings in late spring or early summer. Root one cutting per cell tray or pot. They tend to root in six to eight weeks and should be kept in humid conditions with temperatures between 68 and 77 degrees. They should flower in 12-18 months.

Commonly grown as house plants, Dieffenbachia species are actually tropical evergreen perennials in the arum family. They are distinguished by thick, clustered stems that become woody with age, draped with large, fleshy, spotted leaves. Many people are not aware that the base of the leaf stalks and stems contain a milky or yellowish sap that can cause contact dermatitis in susceptible individuals. To relieve skin irritation, wash the affected area thoroughly with soap and water; if the irritation persists, wear gloves when handling your Dieffenbachia. The plant also contains microscopic, needlelike crystals of calcium oxalate that if ingested by humans or pets can cause burning and swelling of the mouth and throat. People who experience severe reactions are sometimes unable to talk—hence one of the plant’s common names, dumb cane. Before bringing any plant into a home that includes small children or pets, be sure to find out if it is potentially toxic.

The seeds of Tacca—a genus of 10 or so herbaceous perennials from the subtropical forests of West Africa and Southeast Asia, grown for their handsome foliage and unusual flowers—should be sown in the spring on the surface of a porous soil mix at 70 to 80 degrees Fahrenheit. Keep the seed evenly moist. Bat plants can also be propagated in spring by dividing their rhizomes; be sure each section contains a bud.

The plants require a moist, warm environment, and if grown outdoors they will need some shade. Since they are not hardy—the minimum temperature at which they will survive is 55 degrees Fahrenheit—they are often grown in a greenhouse.

Japanese persimmon (Diospyros kaki) is parthenocarpic, which means it is capable of producing mature fruits without benefit of fertilization, or sometimes even of pollination. The resulting fruits will then be seedless. If you planted your tree with other Japanese persimmons, however, cross-pollination will likely occur and the fruits will bear seeds.

The term “parthenocarpic” is derived from the Greek roots parthenos, which means “virgin,” and karpos, which means “fruit.” Notable examples of parthenocarpic fruits include navel orange, banana, and pineapple. Brian Capon, author of Botany for Gardeners, notes that not all seedless fruits are parthenocarpic. Some seedless grapes, for instance, develop after pollination and fertilization, but embryoes abort before seeds enlarge.

Star anise (Illicium verum) is a magnolialike evergreen tree native to Japan, China, and India. Its glossy brown seedpods are star shaped and have a very pronounced aniselike fragrance, hence the common name. In its native environment, the seed pods are burned like incense to scent homes, and they are chewed after meals to freshen breath. The seed pods are also used as a seasoning in Asian cooking and are often an ingredient in Chinese five-spice powder.

The tree may grow to 60 feet in height and is hardy in USDA Zones 7 to 9 and heat tolerant in AHS Zones 9 to 7. It bears small, star-shaped flowers with yellow tepals—petals and sepals that are indistinguishable—in early summer.

Pregnant onion (Allium cepa) is more commonly known as Egyptian or top onion. Its unusual name is derived from the way a dense cluster of tadpole-shaped bulblets form at the tip of the plant’s stem. These small bulbs can be harvested and eaten when the onion tops begin to wilt and dry out. Egyptian onion’s underground bulbs can become rather strong-tasting late in the season, but can be harvested in early spring as green or bunching onions. Plant Egyptian onions in fall by setting out bulblets in well-prepared soil amended with organic matter. They will tolerate a hard freeze so that plants left over from the previous season can sometimes be harvested even into winter.

Neal Peterson, founder of the non-profit PawPaw Foundation, says pawpaw trees are generally self-incompatible—requiring a genetically different tree for successful fertilization and fruit set to occur. In the wild, pawpaws often spread by root suckers and form groves of trees with identical genotypes. Additionally, natural pollinators of pawpaw flowers—bees, flies, and other insects—are not always dependable or available. Trees in a wooded setting are also often heavily shaded and thus less vigorous than trees in the open.

To improve fruit set, Peterson recommends thinning trees around the pawpaws to provide more light, transplanting wild pawpaws from other areas of the woods to offer genetic variability, and hand-pollinating pawpaw flowers when they bloom in early spring. But the best way to ensure the development of quality fruit, Peterson says, is to purchase grafted clones of several pawpaw cultivars and plant them in an area where they will receive full sun.

One of the oldest known cultivated plants, the broad bean or fava bean (Vicia faba) is a legume related to vetch. Native to Africa and the Middle East, it is also known as Windsor bean, Scotch bean, and horse bean.

Broad beans make an excellent substitute for lima beans in cold, short-season areas where the latter cannot be grown successfully. Plant them in the spring as soon as the ground can be worked (at the same time as peas). They need the long cool springs to set their pods; warm weather—above 70 degrees Fahrenheit—inhibits flowering and pod setting. Broad beans will survive frost but not a heavy freeze. Their taste has been described as between that of a garden pea and a lima bean, with rich nutty overtones.

It’s not very common for caladiums to form flowers, but apparently the environmental conditions in your garden were just right for them. Like the related calla lily and Jack-in-the-pulpit, the flowering structure consists of a hooded, petal-like bract called the spathe and a spike called a spadix. The tiny flowers are crowded along the spadix with the female flowers on the lower part and the male flowers above them. Following pollination the plant will form white berries.

Since Amaryllis bulbs do not like to be disturbed, it is best to remove offsets each year. This will also encourage the growth of large, single bulbs. If the offsets are left attached, however, large clumps will eventually form and they will have to be divided. This should be done in autumn, and the bulbs should be replanted with neck and shoulders above the soil surface.

Like most hardy bulbs, alliums are best planted in early fall, but you may get away with planting them in early spring if you can store them in a cool, dry place. Another option is to plant them now in a large container and place it outside or in an unheated garage so they will get enough chilling to bloom. Make sure the soil around them stays slightly moist but not waterlogged.

Some other hardy summer-flowering bulbs to consider include Sicilian honey garlic (Nectaroscordum siculum) and native spider lilies such as Hymenocallis caroliniana and H. liriosome, which are hardy to USDA Zone 7. “Crinum lilies would be really good for Chapel Hill,” says Nancy Goodwin, creator of Montrose gardens in Hillsborough, North Carolina. Crinums and spider lilies have an advantage over some other summer bloomers in that they don’t mind clay soils, and some even thrive with wet feet. Despite references that indicate these bulbs are hardy only in Zone 9 or 10, Goodwin has had no problem growing Crinum ‘Ellen Bosanquet’, C. ‘Milk and Wine’, or Amarcrinum memoria-corsii, a hybrid between Amaryllis belladonna and Crinum moorei. Good choices for lower-growing bulbs, according to Goodwin, are rain lilies such as Zephyranthes candida, Z. flavissima, and Habranthus robustus, which flower after rainfall throughout the summer. Old favorites include Gladiolus, Crocosmia, and, of course, many, many lilies (Lilium spp.)

Even gardening books that talk about this plant, Tweedia caerulea, usually use its former name, Oxypetalum caeruleum. It is also called southern star and blue milkweed, since it is a member of the milkweed family. It is a native of the tropics of South America, so must be grown as an annual in the United States. Not really a vine but more of a subshrub, it has twining stems to three feet tall. Its most spectacular feature is its flower color, described as a powder blue tinged with green that makes it almost turquoise, becoming lilac as it ages.

When he was an amateur hybridizer, David Austin crossed the Gallica 'Belle
Isis' with the Floribunda 'Dainty Maid'. 'Belle Isis' has small, light pink,
very double flowers and is a once bloomer. 'Dainty Maid' produces single
flowers and is a repeat bloomer. Among the seedlings of 'Belle Isis' x
'Dainty Maid', one, in particular, was outstanding. 'Constance Spry', as it
was named, produced surprisingly large, beautiful, pink flowers. The flowers
were deeply cupped in the Old Rose tradition. In addition, 'Constance Spry'
has a strong fragrance described as 'myrrh'. It was introduced in 1961.

'Constance Spry' had nearly all of the qualities David Austin was trying to
achieve, excellent Old Rose flowers with good color and fragrance, all on a
vigorous bush, but it was once blooming. Since the repeat blooming gene in
roses is recessive, a cross between a once blooming old rose and a repeat
blooming rose almost always produces once blooming seedlings, so 'Constance
Spry' was once blooming. However, 'Constance Spry' was crossed with a repeat
blooming rose, and some of the seedlings were repeat blooming. With these
seedlings, David Austin had what he desired, repeat blooming roses with Old
Rose style flowers and good fragrance. So far, David Austin only had pink
roses.

I do not wish to give the impression that all English roses are beautiful
disease-resistant shrubs with large long-lasting old-fashioned flowers. Here
are some of the problems that some or many varieties of English Roses have.

Cut flowers: English Roses can make beautiful cut flowers, but most have two
disadvantages when used as cut flowers. First, most of them have rather
narrow short stems when cut, not nearly as long or stiff as the long-stemmed
Hybrid Teas. Second, the petals are usually more delicate than those of
Hybrid Teas, and some varieties don't last long when cut. 'Heritage' blooms
are famous for lasting only about a day on the bush and only hours when cut.
'Graham Thomas' doesn't last very well either and fades, but 'Abraham Darby'
and Evelyn both have many petals and peform well as cut flowers.

Size: Some English Roses that are medium-size plants in England, where they
were bred, grow very large (often twice as large) in warm climates, such as
the Southern part of the United States. Examples of large plants in warm
climates are 'Graham Thomas', 'Abraham Darby', 'Othello' and 'Evelyn'. This
should be taken in mind when purchasing English Roses.

In your area, April 30 is the projected date for the last killing frost, according to a map published in U.S. Department of Agriculture “Home and Garden Bulletin 202.” This date could differ as much as one to two weeks within 10 miles of your home. It is best to check with your county Extension agent or local weather bureau. Keep in mind that this is the average date for the last frost that will kill established perennials to ground level. When installing tender plants or sowing seeds, wait a few weeks so the soil can warm to a safe temperature.

Your plant is Abutilon. Outdoors, it requires moderately fertile, well-drained soil and full sun.

These plants are not hardy. Sow seeds at 61 degrees Fahrenheit in the Spring. All parts are highly toxic if ingested so be careful. Outdoors these plants grow in fertile, moist, but well-drained soil in full sun.

Blue laceflower (Trachymene coerulea) is listed in older references by its former name, Didiscus coeruleus. It is a member of the carrot family, Apiaceae, and has finely divided leaves on slender, branching, erect stems. The small flowers are in rounded umbels two or three inches across, held aloft on stems one to two feet high. The lacy flower does resemble that of Queen Anne’s-lace, but is pale blue or lavender. The species is a native of Australia and the islands of Southeast Asia, and our references make no mention of it being naturalized in the United States. Catalogs tout it as a cut flower. It is a sun-loving annual or biennial that does best in porous, well-drained soil of moderate fertility. In greenhouses, blue laceflowers can bloom from fall to late spring. Seeds are available from several retail mail-order companies.

The care of English Roses is similar to that of Modern Roses with some
exceptions.

Hardiness: Most English Roses can be grown in Zone 5 or warmer. 'Constance
Spry', 'Mary Rose', 'Charles Rennie Mackintosh' are some of the hardiest
English Roses. 'Graham Thomas' and other yellow varieties may need some
winter protection in cold climates.

Disease: Some varieties of English Roses seem to be rather resistant to
blackspot and other diseases. However, this depends greatly on the
particular variety and climate. In particular, many of the red English Roses
have been rather susceptible to blackspot and other diseases and have been
weak growers.

Planting: While English Roses can be grown as individual plants, group
plantings of two or three plants of one variety planted closely together are
often recommended if there is room in the garden. A group planting will
produce a fuller looking growth and more flowers in an area than a single
planting. An odd number of rose bushes planted in a particular location
usually looks more natural than an even number of bushes.