How to Use 30-30-30 to Fertilize Beginning Roses
- 1). Test soil for roses in early fall, at least three months prior to planting. Roses require loamy soil with a pH range between 5.5 and 7.0. If you must adjust the pH range, the soil amendments will take three months to change the soil. To test soil, dig a soil sample using a shovel from the area where you will plant roses. If you are planting many roses, take several samples by digging 1 quart of soil from multiple locations across the rose bed with a shovel. Mix these samples in a bucket to form a composite sample and collect 1 cup of soil in a plastic bag. Take the bag to your county extension office. An agent with the office will assist you in submitting your sample to a soil laboratory. The test results from the lab will indicate the nutrient levels, soil structure and pH of your soil.
- 2). Break up the soil in a rose bed with a garden tiller to a depth of 12 inches and add soil amendments based on the suggestions made by the soil test. Most rose beds benefit from amendments such as lime to raise the pH of soil or elemental sulfur to lower the soil pH. A 4-inch layer of organic amendments, such as compost and peat moss, will help to make the soil more loamy and well drained. Add a superphosphate at a rate of 3 lbs. per 100 square feet. This will help to encourage root development in roses. Mix these amendments into the soil to a depth of 12 inches.
- 3). Purchase roses for planting in early spring. The earlier roses are planted, the better their chances for survival. Roses may be purchased as bare root plants or as potted plants. Bare root plants are less expensive, but potted roses have a more developed root system and will survive better.
- 4). Unwrap bare root plants and soak the roots in a bucket of water for one hour before planting. Lift potted roses from containers and trim back dead, damaged or diseased roots with pruning shears.
- 5). Open a planting hole in the soil for rose plants that is 15 inches deep and 18 inches wide. For bare root roses, mound up soil in a cone in the center of the rose bed. If you sit bare root roses on this cone and spread the roots across it, the roses will be planted so that the soil line that the plant initially grew in will be the same as the soil line that it is planted in currently. Do not mound up soil for container roses. Instead, sit the root ball into the soil so that the soil line of the container is even with the soil line of the ground.
- 6). Mix 3 oz. of superphosphate, three shovels of compost and the soil that you pulled from the planting hole. Fill in the space between the rose roots and the planting hole with this mix. Work the soil between the rose roots and water to dislodge any air pockets. Mound up an additional 6 inches of soil around the canes to prevent roses from withering while the roots become established.
- 7). Water the plant weekly with a garden hose in the morning hours. Roses need the equivalent of 1 inch of rainfall every seven to 10 days to thrive. Apply a 2-inch layer of bark mulch around the base of roses to help hold in water and smother competing weeds.
- 1). Calculate the amount of 30-30-30 fertilizer to add to the soil yearly. Roses bloom well if given 3 lbs. of actual nitrogen per 1,000 square feet, or .3 lbs. of nitrogen per 100 square feet. Divide 3 lbs. with .30 to get 10 lbs. per 1,000 square feet.
- 2). Divide 10 lbs. per 1,000 square feet by 10 to convert the figure to 100 square feet to make 1 lb. of 30-30-30 fertilizer to add to 100 square feet around rose plants. This is the amount of fertilizer to add per 100 square feet of rose plants per year.
- 3). Divide the 1 lb. amount by the number of times you will fertilize your roses in a year. Most roses are fertilized three times yearly. The first application is in early spring when the roses begin to produce greenery. The second application is in mid-July. The final application is typically in autumn after the first killing frost or in early spring before roses emerge from dormancy. This last application will encourage root development when canes above ground are dormant. Dividing 1 lb. of 30-30-30 fertilizer into three applications will give you 1/3 lb. of fertilizer per 100 square feet per application.
- 4). Spread granular 30-30-30 fertilizer around the base of rose plants near the outer edges of the root system at a rate of 1/3 lb. per application at the correct time. Scratch the fertilizer into the soil lightly using a gardening fork.