Am growing some dry westerners in the wet east USA in a sand bed. Some have suggested 1/4 to 1/2 tsp Osmocote per plant, maybe less on penstemons or oxytropis. Already used some dilute liquid fertilizer.
Charles Swanson Z6a Massachusetts USA
Obviously I'm not going to use manure, but are chemical fertilizers a real or potential problem in lower doses?
How deep are your sand beds?
The reason I ask is that dry western species send their root system very deep and if the beds are not excessively deep they will take their nourishment from the subsoils.
If fertilization is still needed, I agree with the doses and type you mentioned. Chemical fertilizers will cause no problems especially the coated time release types. Over fertilization will give you uncharacteristic growth.
In my dry land garden I do not fertilize any thing. Grow them lean and mean.
Thanks for the note. Sand bed is 14 to 20 inches. I'm going toward clean coarse mostly quartz sand, so I'm thinking it might be low on nourishment and may take a few years for new plants to get down to clay loam below. Lately I've been adding basalt stone dust to the sand, thinking it may provide a variety of minerals.
Some plants do show some fungus or dieback, lately I've got the idea of spaying with a fungicide. Generally hardy cactus and penstemons, seem fairly content and pest free--except voles and penstemons.
Charles Swanson Massachusetts USA
I in a very lean sand bed i can understand your consern about lack of nurisment for the first year or two.
I fertilize my westerners about 2 or 3 times a year, with a dilute fish emulsion. I used to use Osmocote, but I found that it provided food for the plants all season, and they seemed to take longer to harden off for the winters. So now I fertilize just after the snow melts, about a month after that, and around July 4, just to celebrate. I've had excellent success with virtually all of them over the past decade, and we're very similar in climate. To me the key is drainage, not the food or minerals. Give 'em as much drainage as possible and the rest takes care of itself. I've got Eriogonum umbellatum, E. douglasii, E. thymoides, E. cespitosa, Oxytropis lagopus, among others in the garden, and I haven't lost one in several years.
OK sounds good, and obviously very successful.
What product do you use and how do you dilute it?
I use fish emulsion, and I use it as soon as the weather is 'safe' in the spring, which for me is when I can expect no major frost again until fall. Then I feed them again in May and that's it. I simply dilute it to 1/2 recommended strength. Understand that this is 'art' rather than science, and that everyone does it differently, and success is predicated on drainage and sun rather than food. One of my friends down the street from me fertilizes heavily, with a balanced commercial fertilizer that she attached to her watering hose, and she uses it twice (at least!) each year, and her plants do quite well, and are actually larger than mine. I don't know how many she loses each year, but overall she has had great success with cacti and other succulents with her feeding regimen.