America's most popular flower is also one of the very oldest flowers in cultivation. There are more than 2,000 different rose varieties to lure us with their history and fragrance. This is because the rose, like the orchid, cross-breeds readily -- a trait exploited first by nature, and then by horticulturalists. Today, we can choose from old-fashioned favorites, as well as modern varieties that are the result of intensive breeding programs throughout the world. The rose is a flower with a rich past, and an exciting future.

Tea roses and cluster-bloomers (floribundas) usually grow no more than 2 to 3 feet high. Their form is coarse, but they do produce an abundance of flowers throughout the growing season. The hybrid tea has large, single blooms on long, stiff stems, whereas the floribunda has slightly smaller clusters of blooms on stems that are not as stiff.

1. Growth Habit Though roses are usually planted for their flowers, it is important to know what the plant as well as the flowers will look like, in order to determine where it will fit in your garden.

Tea roses and cluster-bloomers (floribundas) usually grow no more than 2 to 3 feet high. Their form is coarse, but they do produce an abundance of flowers throughout the growing season. The hybrid tea has large, single blooms on long, stiff stems, whereas the floribunda has slightly smaller clusters of blooms on stems that are not as stiff.

Miniature roses have tiny flowers, and may be only 10 to 36 inches tall. They are ideal for containers.

Shrub roses, including both the old-fashioned and the modern types, and ground-cover or landscape roses, are generally large and leafy.

Climbers grow from 7 feet to 30 feet in length, and most of them benefit from some type of support.

Tree roses, or standards, are roses that are grafted into a tree-like form with a single stem and a rounded bush or weeping display of flowers on top.

2. Hardiness Northern gardeners need to know exactly how hardy a rose is. Southern gardeners must also watch to see what zones are recommended for each particular variety, because some roses perform very poorly in hot and/or humid weather.

3. Bloom Time Many roses, especially the old-fashioned varieties, have just one flush of blooms per year. Will you be satisfied with a cloud of heavenly pink blossoms for three weeks in June, or do you need your rose to bloom all summer long? This consideration may narrow your choices very quickly.

4. Disease Resistance Selecting a disease-resistant rose is the single most effective way to avoid problems and the need for chemicals. You might start by considering some of the old rose varieties, many of which have natural disease resistance. You can also look to many of the modern roses, which are now being bred for improved disease resistance.

5. Stem Length This may seem like an odd consideration, but it's important if you are growing roses for cutting. The traditional florist rose is a hybrid tea, and it is the only type of rose that flowers on a long, stiff stem. All other roses have shorter, weaker stems, which gives them a more casual -- some believe more beautiful -- presence in a vase.

Can I grow roses in a spot that is sunny for only part of the day?

For most abundant blooms and greatest vigor, roses need to receive six to eight hours of direct sunlight each day. In hot climates, they will appreciate receiving protection from the most intense afternoon sun. In cool climates, a fence or a warm south- or west-facing wall can add enough extra warmth to boost flower production and reduce winter damage.

My soil is quite sandy. What do I need to do to make sure it's good for growing roses?

Sandy soil usually drains well, so you've got a good start. Roses need good drainage. However, roses also like rich, moisture-retentive soil, with a pH between 6.5 and 7. So, you should add compost to create a loose texture with a high organic content. If your soil is heavy (clay) and wet, you may want to consider planting your roses in raised beds.

I've been using a sprinkler to water my roses, but my neighbor says drip irrigation is better. Is this true?

The problem with overhead watering is that it can spread diseases, such as blackspot and powdery mildew. The best way to water your roses is with drip irrigation. It concentrates the water at the root zone where it is needed, and keeps the foliage dry to minimize disease problems. A good, thick layer of organic mulch will help conserve moisture, reduce weeds, and encourage healthy root growth. As the mulch breaks down, it will also add organic matter to the soil.

How often should I fertilize my roses?

Roses are heavy feeders, and will benefit from a steady supply of nitrogen, phosphorus and potassium. You can provide these nutrients with either liquid or granular fertilizers, at a ratio of approximately 5-8-5. In most cases, regular applications of compost, rotted manure, fish emulsion and seaweed extracts will provide roses with all the nutrients they need. These organic amendments also help to moderate pH imbalances and stimulate beneficial soil life. Other organic amendments favored by rose growers include greensand, black rock phosphate and alfalfa meal.

I've heard that roses get have lots of pest and disease problems. Are they difficult to grow successfully?

Yes, pests and diseases can be challenging. Prevention is the best way to avoid problems. Here are the key factors:

• Choose disease-resistant varieties.
• Keep plants in healthy condition (well-fertilized and well-watered).
• Maintain good air circulation by pruning to keep an open framework.
• Avoid overhead watering.
• Remove any diseased foliage or spent flowers.
• For persistent pest problems, you can use botanical insecticides such as sabadilla, neem, rotenone, and pyrethrins. These are broad-spectrum controls, meaning they kill many types of insects, both good and bad. Though they are organic, these controls are potent and should be used sparingly.

Although some roses only bloom once a year, most of the modern hybrids are repeat bloomers, which means they bloom in waves through the summer. By creating the best-possible growing conditions, you can ensure more flowers.

• Remove faded flowers. This prevents the formation of hips (or seedpods) and redirects the rose's energy into making more flowers.
• Be sure to water your roses regularly -- especially if rainfall is insufficent. They need at least an inch a week. Avoid overhead watering, which wets the leaves. Use drip irrigation instead, and conserve moisture with a layer of mulch.
• Maintain a regular fertilization schedule. Roses are heavy feeders. You can fertilize with either liquid or granular fertilizers with an NPK (nitrogen-phosphorus-potassium) ratio of about 5-8-5. In most cases, regular applications of compost, rotted manure, fish emulsion and seaweed extracts will provide roses with all the nutrients they need. Other organic amendments favored by rose growers incldue greensand, black rock phosphate and alfalfa meal.
• Keep pests and diseases under control. A plant that has to fight insects or disease is less vigorous -- and less floriferous. Prevent diseases by maintaining good air circulation around the plant, keeping the foliage dry and removing any diseased foliage or spent flowers.

Watch for the Big Four: Aphids, Beetles, Mildew and Blackspot

Roses sometimes get a bad rap for being prone to pests and disease. But with just a little extra care, they'll reward you with beauty and fragrance. Just make sure you know how to control the four most common problems:

Aphids

(Size=less than 1/10 inch)
Aphids most often attack the buds of roses. Small infestations can be controlled with a blast of water or hand-picking. Found throughout the United States, these small, soft-bodied insects may be pale green, pink, black, or yellow, depending on the species. Some stages of the life cycle are winged, others wingless. Aphids feed on a wide variety of plants, including roses. Clustering on tips of new growth and leaf undersides, they feed by sucking out plant juices, causing leaves to become distorted and yellow. Aphids secrete a sugary fluid called honeydew that attracts ants and may cause the growth of a sooty black fungus on leaves. In small numbers aphids do little damage, but they reproduce rapidly. Control while the population is still small.

Controls: Aphids are easy to control. Simply washing plants with a strong spray of water will reduce their numbers dramatically. Insecticidal soap is more effective. Horticultural oil will eliminate them. When spraying, be sure to cover leaf undersides. A variety of natural insect parasites and predators also reduce their numbers, the main reason you don't want to be overly aggressive with sprays.

Japanese Beetle

(Size=1/2 inch)
Still primarily a pest of the eastern U.S., they turn up west of the Rockies from time to time. They're a problem for gardeners because they have an appetite for a wide variety of plants. Adults feed on just about every kind of flower or vegetable, sometimes in disturbingly large crowds. They chew out the leaf tissue between the veins, leaving a lacy skeleton. When they attack roses, you'll often find them in the center of the bud, eating the tender petals. Prior to pupating, the white, 1-inch long, C-shaped grubs live in the soil and feed on the roots of most all plants. Grubs are often a problem in lawns.

Japanese beetles can be devastating. Once you see the first beetle, look for signs of more, which are sure to follow. Be sure to check in the buds of opening roses, a favorite food of the beetles. Because the beetles are relatively large and slow to react, they are easy to pick off roses by hand.

Controls: There's a cockroach-like relentlessness about Japanese beetles that can get under a gardener's skin. But we're not helpless. The beetles are relatively big and easy to see, and they're not real quick. They are pretty easy to just pick up or knock into a can of soapy water.

Yellow target traps baited with a pheromone attractant work, but sometimes too well. Don't place one near your garden or you'll be pulling beetles in from all over town.

Deter adult beetles from feeding by spraying neem oil. Use parasitic nematodes in lawns and garden beds for control of grubs.

Powdery Mildew

This fungus disease occurs all over the North America and infects a wide variety of plants. A powdery white growth covers the upper surface of leaves, which eventually turn yellow and dry. Older leaves are usually infected first. The fungus competes with the plant for nutrients, reducing flowering and weakening or even possibly killing the plant if infection is severe. This disease usually develops late in the season on mature plants and thrives in both dry and humid weather. It can spread rapidly.

Prevention And Control: Choose disease-resistant roses. Potassium bicarbonate fungicides are effective when applied according to label directions.

Blackspot

This fungal disease is named for the black spots that form on the leaves. Evenually, the blackened areas are surrounded by yellow, and the damage covers the whole leaf. In severe cases, the plant can lose all of its leaves. High humidity and heat create ideal conditions for the spread of the disease because the spores only travel in water droplets.

Prevention And Control: Prevent problems by spraying every 10 to 14 days with neem oil or a baking soda-based fungicide. Of the two products, neem is better at controlling an outbreak in progress. Both are good for prevention. Avoid watering the leaves, or water early in the day. Be sure to remove and destroy diseased foliage. Ensure good circulation around your roses by pruning to open the center of the plant. Roses should not be packed in among other plants.