I saw a recommendation for 3-1-2 fertilizer for roses, so would Dyna-Gro 9-3-6 be a good fertilizer to use for roses planted in containers?
How often should I be applying this, and would a maintenance dose be about half of a full dose?
The Dyna Gro 9-3-6 is good (maybe even superior) fertilizer for just about anything grown in a container. The exceptions would be Australian native P sensitive plants and blueberries.
For roses or other woody plants I would follow their 'production routine', which is to mix 1 tsp. per gallon of water, once a week.
Because I grow altogether too many woody plants in containers and using the Dyna Gro weekly or more often is excessively expensive and time consuming, I prefer to use Osmocote Plus. One application in spring lasts the entire growing season and it also has a full range of micronutrients. A slightly different NPK ratio but still a perfectly acceptable and highly functional fertilizer.
@gardengal48 Are you using the Osmocote in containers at around one tablespoon per gallon? So a large 10-gallon pot would get 10 tablespoons of Osmocote Plus on the surface? That's a lot of fertilizer!
Lordy!! I've been using the stuff for so long, I no longer measure. LOL! That amount seems excessive to me. I'd estimate I use about a half cup (give or take) for my larger containers and then scale downward for the smaller ones. After many years of following this practice, I can't see any deficits plant-wise so I assume I must be doing something right.
It is not a requirement to be precise :-) Few things in gardening do require precision.....
@gardengal48 Your 1/2 cup is eight tablespoons, which is all about the same ballpark. I am not trying to be exact. I just want a rough ballpark and you gave me that. Thanks.