That gets too scientific for me! For the ones in the ground I use nothing. For the ones in the pots, I use nothing, or Plant-tone if I remember, or maybe some Osmocote, which I'm trying this year.

Waste of money. If you want to use an organic fert use something like Plant Tone 5-2-2 or Soybean meal 6-1-1. If you want to use a synthetic fert use regular 10-10-10. At this time of year you should not use a slow release synthetic fert, just the regular cheap kind. Do the 10-10-10 about every two weeks if you use that. Plant Tone would be good for the remainder of the season.

Steve

Thanks guys-saved me money. I'll use plant tone, since I always have some handy.

I use some Shake n feed by Miracle Grow when I plant a new one,but after that,nothing. My woodland garden gets plenty of nutrients from falling tree leaves every year. Phil

Thanks phil-If there is one thing I have in the fall is tons of falling leaves, I had 40 contractors bags full of leaves from my yard. the rest I put in the compost. Thats not counting the inordinate amount of pine needles. I guess nature takes care of its own.