Have any of you used Mycorrhiza fungi with your roses?
If you have, did you notice any increased resistance to mildew, spots or insects?
If you used a fungicide on your plants, do you feel this inhibits the action of Mycorrhiza fungi?
I use it with my seedlings from day one. The peat mixes are sterile (do not contain any naturally occuring Mycorrhiza fungi) so this is when the outside addition of Mycorrhiza fungi can do the most good.
I do not use fungicides.
I swear by this when planting bareroot trees and shrubs. It is essential when trying to avoid rose replant syndrome too. I believe the myccorhizae need to have direct contact with the roots so I also use it when potting on seedlings. I have not used it with the intial pricking out of seedlings.I have only used granules though (I believe you can buy a liquid formulation which might be more efficaceous for an application to the potting medium).
rose replant syndrome … what is this??
when we grow roses, the roots have some exudation or something (it is not scientifically clear what really causes this) so if we replant roses in the same area, they fail to thrive. A bit like doing a crop rotation. The only ways round this used to be either total soil removal, chemical sterilisation or some attempt at isdolation by planting new roses in a cardboard box using clean mix and plunging it into the old rose bed. Mycchorhizae has been found to nullify RRD (I know this means something different in the US).
It is common in Europe but the US seems free of this affliction…and I guess Oz too.
Hmmm… that is a worry! thanks for sharing, Campanula!
Title: Growth inhibitor accumulates in the nutrient solution of closed system rose cultivation.
Author: Sato, N.
Authors affiliation: Shizuoka Agricultural Experiment Station, 678-1 Tomioka, Shizuoka, Iwata, Japan.
Published in: Acta Horticulturae (2005), 697(Proceedings of the International Symposium on Soilless Culture and Hydroponics, 2004), pages 511-516.
Abstract: "The circulating soln. was collected and analyzed for its nutrient concn. Three types of solns. were prepd. for the bioassay. One was the circulating nutrients soln. Activated charcoal was added to second soln. The third soln. was prepd. to the analyzed formula of nutrients soln. using distd. water. The rooted cuttings of rose were planted in each soln. and incubated in the growth chamber. The rate of change of fresh wt. before and after the incubation was biggest for the prepd. soln., which does not include the circulating soln. The fresh wt. growth rate was smallest for the circulating soln., and the results for the activated charcoal treatment was between them. Since the activated charcoal does not have a sterilization effect, it is possible that the growth inhibitors accumulated in the soln. during the circulating cultivation of roses. "