Mulch

by Linda Walton, Shasta Rose Society, Past President and a Master Rosarian

This article was published in April 2020 issue of “The Fifth Leaf”, editor Barrie Freeman.

I am in the process now of applying mulch around each rose bush in my garden. I am using an organic potting mix with 12-12-12 fertilizer and adding about 1⁄2 bag of alfalfa pellets to the mix. The mulch has coconut fibers, perlite, and composted poultry manure. When I am done with this step, I’ll cover the beds with about 3 inches of bark, which will help control the weeds, help hold the moisture in the soil and conserve water.

Mulching is nothing more than layering organic materials over the soil and is so beneficial to the rosebushes and the beds in which they grow. Once you begin mulching, adding dry organic materials each spring becomes easier as mulch becomes looser and more amendable to additives. In well mulched beds, it’s easy to rake circles around the bushes, work in dry fertilizer and cover the whole area with fresh materials for the coming season.

No mulch material is more beneficial than aged manure. As it decomposes, it warms the soil, which helps accelerate the uptake of nutrients by the rose bushes. Applying alfalfa pellets that have no additives such as sugar or molasses provides a natural nitrogen to the plant. The roses love it. Other organic materials that decay into humus can serve as mulch: compost, aged bark, leaf mold, rice hulls or peat moss, mushroom mulch, etc. Soil with no blanket of mulch becomes hard and compacted, and fertilizer can’t be scratched in. Compressed soil also inhibits the development of feeder roots.

Roses are insatiable drinkers, but they prefer long drinks to everyday short watering. Feeder roots develop on rosebushes no matter how they’re watered, but long roots develop only if forced to search deep for water. How often you should water depends not only on how much mulch you have applied to your rose beds, but where you garden, and the temperatures. In the summer in Redding, CA when the temperatures are above 100 degrees, I need to water sometimes twice a day, especially my potted roses.

The only thing roses love more than water is food. When properly fed, roses reward us with abundant blooms. Because I have so many roses, I like to use dry fertilizers such as 12-12-12 or 15-15-15 on my rose beds, and I like to use a slow release fertilizer on my potted roses. These fertilizers have a balanced blend of Nitrogen (N), Phosphorus (P) and Potassium (K). I also like to use a liquid fertilizer after each bloom cycle to encourage more bloom, especially before a rose show.

Also, it is important to test the pH of your soil. Roses thrive in soils with a pH around 6.5. Test kits are available at local nurseries but may not always be foolproof. If you have never had your soil tested by a soil laboratory, you may want to do that to find out your garden’s overall pH. Once you have corrected the pH of the soil in which your roses grow, then you can fertilize accordingly.