The Path to Organic Roses, Part II
by Jack Shoultz
Originally published in California Coastal Rose Society Newsletter
by Jack Shoultz
Stacking tray worm bin.
Q: How do the effects of using organic fertilizers differ from using chemical fertilizers?
A: There are many differences in how and what happens when using organic fertilizers compared to chemical fertilizers. The first that may be noticeable will be the speed of growth. To compare what happens in regards to the growth we need to focus on what happens in the soil after you apply fertilizer. With chemical fertilizers, they are usually either mixed in liquid form or become activated when watered in the soil. The Nitrogen is readily available and taken up immediately by the roots. If the roses were not watered before the fertilizer was applied or the soil was not moist the rose would take up larger quantities than necessary of Nitrogen perhaps causing leaf burn. As the plants are watered the fertilizer that is not able to be utilized by the plants will be washed on through the root system and eventually past where it is usable by the plant. The supply of Nitrogen that is available at this time will cause a quick spurt of growth depending on the concentration. The higher the N in the N-P-K the more will be available at one time. For Example: 15-15-15 will have more available then a time release, but less then a blue liquid (ie Miracle Gro) which is already in liquid form so will be available even quicker, but will wash out quicker.
When an organic fertilizer is applied, it is usually best scratched into the soil to help activate the process. This process is the beginning and the increasing biological activity in the soil by introducing organic material. This organic material must be broken down to become usable to the roots. Organic material is anything that originated as living matter. For example a good source of organic Nitrogen is Alfalfa or Blood Meals. There are others, but these are recognized and used for growing roses. There are several commercial products that are combinations of natural materials and have all the major nutrients and many micro nutrients. Compost is one of the best all around soil amendments that can be used. What all of these things do in the soil is not only make nutrition available for the plants, but to build your soil. The organic materials become incorporated into the soil and create an environment in the soil that is increased the more biological activity there is in the area. In hot weather the activity increases and conversely in cold weather it slows down. There needs to be adequate moisture for the activity to be at its optimum. One of the best ways to begin this activity is to incorporate it in the soil as the bed is prepared, but most of the time this in not an option. With an established bed working the nutrient rich material with humic acid and/or mychorrizae into the top inch of soil and putting down a 2-4" layer of good quality mulch will start the process. If you do not have abundant earthworms you should see a sizable increase of them and then you can be sure the condition of your soil is improving as worm castings are one of the quickest ways of putting the oomph in your soil. And an advantage of organics is that you can do this any time of the year. If you have not started organics yet then now is a good time. Last year I started a new garden in the fall and put down 4 cups of organic fertilizers. This is about twice the normal amount. The results of this was a new set of basil breaks on several of the roses in the garden and strong steady growth on all others. With organic fertilizer the nutrients become part of the soil and is available as the rose needs them. This allows for a constant steady growth instead of the quick spurts you get with the chemical choice. This growth makes for stronger canes with more disease and pests resistance. The cell structure when the growth is like this is compact and stronger. There are also liquid organic fertilizers that are available to the plants as immediate food. These are a good choice when beginning the process of shifting over from chemical to natural products to fill in while the newly introduced products are being broken down in the soil.