I’ve used chemical fertilizer NPK 5-1-5 and earth worm castings, but some of my roses new growth looks like signs of chlorosis.
Kardinal Kolorscape
Jude the obscure
Little artist
Just want to check before I add more fertilizer. Some of my roses leaves look totally fine, like pure magic pictured below
Does your fertilizer have micro-nutrients as well as The Big 3? Looks a bit like an iron-deficiency, but I’ve seen freshly-opened young leaves like that colour up well just as a matter of course, so hard to say. I use bagged manure as top dressing for my containers, adding some each spring as they awaken, then again in fall before the rains start. I often incorporate low perennials as well, to keep the roses’ roots cooler.
You’re in an entirely different climate, so what works for me may not for thee…
So these are the ratios:
5:1:5 (25)
113 g/kg N; 22 g/kg P; 113 g/kg K
17 g/kg Mg; 14 g/kg Ca; 120 g/kg S
It also says that it has trace-elements Iron, Boron, Manganese, Molybdenum, and Zinc) Contains a high percentage of carbon in the form of humic acids. But as the amount isn’t stated I doubt that it has enough of these trace elements, I think you may be correct
@HighVeldRoseGrower
I’m also thinking it’s a chlorosis problem. Although there’s often enough iron in the soil, the plant can’t absorb it because of the high pH value. However, the leaf discoloration looks very similar when the soil is too acidic. That’s happened to me already. So before you jump to conclusions, you should conduct a pH test to determine exactly which direction the correction should go. Only then would I consider increasing the fertilizer application, if necessary.
I’ll second @Roseus’s comment about the pH; especially because container-roses usually get a LOT of water run through them, which makes for acidic conditions.
