When To Fertilize Delphiniums And Should I Spread Compost Around?

Question

Hello! I’m in zone 4b, (maybe 5 now?) in MN and planted delphiniums last fall. I noticed some bud and leaves are popping up. Typically the last hard frost here is May 10 but looking at the weather it looks somewhat ‘warm’ at night. Do I fertilize the delphiniums and stake them now with bud growth forming? Or is there a key time to fertilize these when more leaves appear? Do I also need to spread compost around the perimeter along with the fertilizer? Thank you!

Answer 1

You can fertilize now with compost or use a general fertilizer such as a slow release 10-10-10. Here is more on their care:

https://www.gardeningknowhow.com/ornamental/flowers/delphinium/growing-delphinium-plants.htm