Gardening Interview Preparation Guide
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Gardening Interview Questions and Answers will guide us now that Gardening is the practice of growing plants. Ornamental plants are normally grown for their flowers, foliage, overall appearance, or for their dyes. Useful plants are grown for consumption such as vegetables, fruits, herbs, and leaf vegetables or for medicinal use. A gardener is someone who practices gardening. So learn Gardening by Gardening Interview Questions with Answers.

33 Gardening Questions and Answers:

1 :: What is the best time to cut down Clematis? I have several that I want to cut back this year, but I don’t know when the best time to do it is.

Pruning Clematis depends upon what kind you have. Different varieties are pruned at different times of the year. First of all you need to identify when your Clematis blooms and what kind it is. Those that bloom on old wood (C. florida, Montana and patens) need nothing beyond removing dead wood. C. lanuginose, jakcmanii and viticella bloom on current season wood and may be cut back in spring before growth begins.

2 :: I am trying to get some information on Manettia cordifolia or M. inflata (firecracker vine). How do I propagate them, and where can they be obtained?

Manettia cordiflora can be propagated by taking stem-tip cuttings when the plant is in active growth, usually around mid-summer. Nodal cuttings are more likely to succeed, since some plants will not root internodally. Prepare each cutting from new growth, up to 4 inches long, by making a clean cut just below the node. Insert carefully in planting medium, water thoroughly with a fungicidal solution so that the medium is moist right to the container bottom.

Semi-ripe cuttings are used by taking the current season’s growth that has begun to firm; the base of the cutting should be quite hard, while the tip should be actively growing and therefore quite soft. Take semi-ripe cuttings in mid-to late-summer or even in early autumn. Take between 21/2 to 4 inches for the cutting. Remove the side shoots, and trim the cutting. Wound the stem and apply a coating of rooting hormone, shaking off any excess.

Semi-ripe cuttings may be rooted in a variety of situations. One suggestion is an outdoor nursery bed that has been amended with soiless potting mix and can be covered and protected so that the cuttings don’t scor or dry out. They require a humid environment for the rooting process to take place. A cold frame or container will work well also. During the winter inspect the cutting regularly and remove any fallen leaves. Water if the medium shows signs of drying out. Gradually harden off the cutting in spring before placing it in the garden.

3 :: Every year I have beautiful green grapes on my vines, but before they ripen they turn black. What can I do about it?

It sounds like you have the vintner’s ancient scourge, grape black rot. It usually starts with small spots on the foliage that enlarge and are surrounded by a darker brown border. Spots also appear on the fruit, but, as you noticed, not until they are about half grown. They enlarge quickly, rotting the entire grape in a few days. The diseased fruits turn black, shrivel, and dry up; they look very much like raisins and are known as mummies.

Grape black rot is caused by a fungus, Guignardia bidwellii, and is a serious problem for grape growers, since all cultivars are susceptible. Wayne Wilcox, a specialist in grape diseases at Cornell University in Ithaca, New York, explains that sanitation is of utmost importance for control. The fungus produces two types of spores: The overwintering spores survive on mummies and these are airborne, thus any infected fruit left on the ground or on the canes becomes the primary source of infection. Later, the disease is further spread through waterborne spores that develop on infected fruit. Remove all mummies from the vines and from the ground beneath. Mulching to cover any remaining overwintering spores creates a physical barrier that will help reduce infection.

4 :: A friend wants to start a grape vine from a set of vines growing at his mother’s house. Should we start from seeds, or would it be best to take cuttings of the old vines?

Although grapes can be propagated from seed, this is rarely done because most grape plants are cultivars and won’t come true from seed. But you have three other options. The first option is to take hardwood cuttings. All grapes grown in the U.S., except Muscadine, can be propagated from hardwood cuttings. In the winter, take one-foot cuttings that have three buds and store them in moist sand or sawdust until early spring, when they should be planted with the top bud level with the surface of the soil. The cuttings should produce vines by the end of the first or second season.

Your other options are to take softwood cuttings or to layer a vine. Both methods work with all grapes, including Muscadine. Softwood cuttings should be taken before the stems harden in early summer and planted immediately. Layering involves taking a vine growing on the parent plant, breaking—but not severing—it at a node, and burying the node in the soil alongside the parent plant. Once roots form—usually within a year—the new plant can be separated and transplanted.

5 :: How can I propagate a Mandevillia?

Sow seeds at 64-73 degrees Fahrenheit in the spring. Root softwood cuttings in late spring or semi-ripe cuttings with bottom heat in summer.

6 :: I’ve noticed that the ‘Marguerite’ and ‘Blackie’ cultivars of sweet potato vines are readily available in the trade. Are the swollen underground roots of these cultivars edible like a “normal” sweet potato? Can you propagate the sweet potato from these roots?

Unlike their agricultural counterparts, Ipomoea batatas ‘Marguerite’ and ‘Blackie’ are bred for ornamental properties rather than edible roots. ‘Marguerite’ is grown for its broad, heart-shaped, chartreuse foliage on trailing vines, and ‘Blackie’ is becoming a favorite in the garden for its dark purple, deeply lobed foliage that makes a great companion for plants with brightly colored flowers or foliage.

According to Janet Bohac at the USDA’s Vegetable Laboratory in Charleston, South Carolina, ‘Marguerite’ seldom produces a “usable” edible root and ‘Blackie’ almost never does. If, by chance, such a root is produced, there is no reason it could not be eaten.

Bohac adds that while it is possible to propagate these varieties from slips produced by their roots, propagation from cuttings is much easier.

7 :: The garden section of one of my magazines referred to a planting of tweedia. It looked beautiful, but I can’t find the plant listed in any of my gardening books. Can you tell me a little about it?

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.

8 :: What is a good red English Rose?

David Austin has had mixed success until recently breeding red roses. Most
older red English Roses (such as 'Fisherman's Friend', 'Prospero, 'The
Squire' and 'William Shakespeare') have produced beautiful fragrant dark red
flowers on weak plants that are disease-prone (especially to blackspot).
Recent crosses, especially with the vigorous and disease-resistant Mary
Rose, have attempted to improve on those weaknesses and seem to have
produced some very good new red English Roses, 'The Dark Lady', 'The Prince'
and 'L.D. Braithwaite'.

* The Dark Lady
* The Prince
* L.D. Braithwaite

'The Dark Lady' (1991, 4'x5', 'Mary Rose' x 'Prospero') has flowers that
have been described as dusky crimson or deep pink. It has a strong Old Rose
fragrance. It is a very good repeat bloomer.

'The Prince' (1990, 2.5'x3', 'Lilian Austin' x 'The Squire') has some of the
darkest flowers of any rose, described as either dark red or purple-red. It
is very fragrant. It is a good repeat bloomer, but the flowers have a short
vase life. Its glossy modern-like foliage may have problems with blackspot.
It is a very small bush, even in the warm climates, so it is probably best
planted in groups of three (or more). It may be a good candidate for
planting in a half-whiskey barrel.

9 :: What kind of care do English Roses need?

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

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.

10 :: What can you tell me about the blue lace plant? It looks like Queen Anne’s-lace, except it’s sky blue. I was told that it grows wild in northern Alabama and into Tennessee, and fields of it are just mowed down.

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.