Grow Roses in Santa Fe

By: Katherine O’Brien, ARS Consulting Rosarian

Growing roses in Santa Fe can be as complicated as you make it. For easy, choose a species rose such as our native Rosa woodsiiand grow it like you would most native plants, giving it sunlight and enough moisture to start it and sustain it. Rosa foetida, the genus of the popular Austrian copper and Persian yellow roses, also thrives in Santa Fe’s high and dry climate without much fuss.When selecting a hybrid tea, floribunda, climber, or shrub rose, you need to put a bit more thought into the project. Roses like sun but not a lot of wind or reflected heat, so choose a site in your yard with these qualities. Soil that contains a high percentage of organic matter, a neutral pH, and good drainage is preferable. In Santa Fe, we usually need to create this soil by incorporating compost, magnesium sulfate, and greensand into our existing subsoil. Roses also require regular watering throughout the year. More roses die in Santa Fe from insufficient water during winter than for any other reason. In the warmer seasons of the year, irrigation systems can deliver the water. However in winter, when the irrigation system is turned off, a means must be devised to supply water to rose bushes at least every two weeks.Roses are grown for their beautiful and often fragrant flowers. To achieve abundant florescence, the rose plant needs a steady supply of nutrients along with regular watering. Phosphorous is the macro-nutrient that promotes both rooting and flowering. Place either superphosphate or bone meal in the hole at the time of planting to give roots immediate access to phosphorous, as this nutrient moves slowly in the soil. A complete fertilizer containing a balanced proportion of nitrogen, phosphorous, potassium, plus micronutrients, should be applied in early May to boost growth development in the plant. The rose flowers occur most abundantly on vigorous new growth. Early fertilization with a complete fertilizer promotes this growth. Rose plants can also be fertilized in June, before the hot weather begins. Avoid fertilizing during the hot summer months to allow the plants to go into semi-dormancy. As the weather cools at the end of summer, a fertilizer higher in phosphorous and lower in nitrogen can be used to prepare the rose for winter.In addition to fertilizers, well-aged composts and manures supply nutrients to the plants. They also add necessary organic matter to the soil. These can be worked into the soil beginning in late June. Fish emulsion and seaweed fertilizer are especially good for new rose plantings as they are easily absorbed by the plants and supply valuable minerals. Organic fertilizers are preferable as they do not interfere with the soil’s microbial activity.In Santa Fe, rose plants are best pruned in early April, when the danger of a heavy frost has passed. As different types of roses require different pruning methods, it is best to learn how to prune by working with experienced rose growers. Free pruning workshops are offered in April both at the Harvey Cornell Rose Garden and at Railyard Park.Santa Fe’s high-desert climate results in daily temperature extremes and long periods of dryness. To moderate soil temperature and help maintain moisture content, organic mulch needs to be applied at a depth of two inches over the rose’s root system. The mulch should be low at the plant base, not actually covering the canes. In the winter, rose canes can be covered with mulch, as the mounded organic matter protects the canes and plant graft from cold damage.The good news about our dry climate is that fungal diseases, which can plague roses in wetter conditions, are rare and easily controlled. Neem oil can be used to mitigate mildew. Dispose of affected foliage to avoid re-infecting the plant. Neem also works as a pesticide for controlling both aphids and thrips. Many rose gardeners control pests with hard blasts of water directed toward the bug-laden plants. Gophers are less easy to deal with, and rose wood is very attractive to them. Use hardware cloth in and a couple of inches above the planting hole when planting roses in a gopher-prone area.Additional information on growing roses is available from the Santa Fe Rose Society (505-988-4614).