Growing Roses

Introduction
Planting and Early Care
Maintenance
Irrigation and Fertilization
Grooming
Pruning
Cutting Flowers
Pest Management

Introduction

Here in Florida, roses grow and bloom year-round in the southern and central parts of the state and for at least nine months of the year in the northern part.

Success with roses depends upon selecting varieties that perform well in Florida and conform to your lifestyle. Roses can be generally divided into two types: low- or high-maintenance. Low maintenance roses thrive with minimal care and include the "old garden roses" (OGRs) and shrub roses. These easy-to-grow types produce more open and informal blooms compared to the "florist-type" flowers of hybrid tea, grandiflora, floribunda and polyantha roses. These latter "modern roses" demand frequent grooming, fertilizing, watering and spraying.

Planting and Early Care

Local nurseries typically sell potted roses year-round, whereas dormant, bare-root plants are usually available from October - March. Roses can be planted year-round except in north Florida, where planting is best delayed until early spring.

Roses in Florida grow larger and require more space than in other locations. The space allowed for different plant growth habits ranges from a circle of one foot diameter for the smallest shrubs, to a circle eight feet in diameter for the largest.

Dig a hole as deep as the root ball from the container and gently loosen circling roots. Plant the rose at the same depth that it was growing in the container. This ensures that the graft union (if it is grafted) remains well above the soil. Irrigate frequently for 6 - 8 weeks to establish.

Maintenance

Cold-protection methods commonly used in colder climes are unnecessary in Florida since winter injury to mature wood of established rose bushes rarely occurs. More flowers are produced during summer than during cooler seasons, but flowers are larger, more intense in color, and have more petals during cooler periods of the year.

Irrigation and Fertilization

Frequent application of water is necessary for modern roses and even low-maintenance roses will benefit from an occasional irrigation during drought periods. Micro-irrigation systems such as drip tubing or micro-sprayers are ideal since the foliage stays dry and less prone to disease. When overhead sprinkling must be used, water early enough for the leaves to dry before sundown.

Fertilizing varies depending on the season, the location, and the size of the plants. Select a fertilizer formulated for roses, preferably one containing micronutrients and controlled-release nitrogen. There is little research on growing roses in Florida, but rose growers usually recommend that roses should be fertilized once a month from mid-February to mid-November except in south Florida where monthly applications can be made year-round. Apply one cup of fertilizer per plant per application or 1/2 cup bi-monthly; reduce this amount for small plants.

Adding organic mulch around roses will hold moisture in the soil, reduce weed growth and provide some nutrients to the plants.

Grooming

Grooming is a regular feature of rose culture and the frequency will depend on the type of rose and your expectations. Grooming consists of selectively trimming your plants at monthly intervals to keep them healthy, attractive, and productive. Removing faded flowers improves the plants' appearance and prevents fruit development. Grooming conserves food material for additional growth.

To produce exhibition flowers, remove the lateral flower buds as they form, allowing only one bud to mature on each stem. To regulate when particular varieties bloom, pinch out all flower buds as they form until twenty-eight to thirty-four days before flowering is desired.

To encourage growth and to help to establish a new plant, remove flower buds during the first two months after planting. The first flowers allowed to develop should be cut with short stems so that as much foliage as possible on the plant. Plants should be well established before flowers are cut with longer stems, and then only cut the length of stem needed.

Remove suckers--leafy shoots--that develop from the rootstock below the graft union by breaking them off rather than by cutting in order to remove all basal buds. Rootstock suckers can be recognized by their location and their different leaf appearance. To learn more, contact your county Extension office.

Remove dead wood and canes showing symptoms of stem disease as soon as you notice them. Cut the affected part back to the healthy wood and remove the affected part from the garden area.

Pruning

In central and northern Florida, prune your roses once each year during December or January. In southern Florida, you may need to prune twice a year to keep plants to a manageable size. These two prunings can be scheduled during March and late August to avoid interrupting winter flowering.

Major yearly pruning consists of removing twigs and branches that are dead, diseased, injured, unsightly, or thin and spindly, as well as some healthy top growth. Shortening main canes and lateral branches and removing small twigs and some of the oldest canes improves the plant's form, regulates its height, and produces better light conditions within the plant.

Leave at least half the length of each main cane that is one to three years old. The first flowers can be expected eight to nine weeks after pruning.

To avoid dieback and encourage rapid healing, pruning cuts should be made just above a dormant bud (eye). When an entire branch is removed, make a smooth cut at the point of juncture.

Cutting Flowers

Before cutting flowers, consider the arrangement in which they are to be used. Larger, more open flowers to be used low in a container need less stem length than tighter buds to be used for height.

Cut buds after the green sepals fold back toward the stem and the outside petals loosen and start to unfurl. Blooms cut in tighter bud will fail to open.

To cut flowers, use a sharp knife or pruning shears. Make a clean cut just above a well-developed, five-leaflet leaf. Dieback may result from leaving a ragged cut or a long stub above the dormant bud.

Pest Management

The most serious problem with roses in Florida is a fungal disease called black spot. This leaf spot disease thrives in humid, wet weather and must be managed preventatively or infected plants will lose leaves, decline and possibly die. Sanitation plays a major role in managing black spot infections on susceptible varieties.

After the winter pruning, remove all leaves from the plants, and rake the area beneath the bush to remove dead and diseased leaves that have fallen during the year. Re-mulch immediately to create a physical barrier between the plant and the fungal spores on the ground, which otherwise will splash onto the plant and re-infect it. Begin spraying as new growth emerges and continue throughout the growing season. Most low-maintenance roses are resistant to this disease to a greater or lesser degree and will survive with few to no sprays. Black spot should also be controlled by irrigating with drip irrigation, which helps keept the foliage dry and less susceptible to fungal infection.

Other common pests of roses include aphids, spider mites, caterpillars, and thrips. Frequently monitoring your roses will help you detect early infestations.