Do you trust this advice from Swan Island
I purchased several tubers from SI this year and followed their instructions for container planting, namely, to mix two parts garden soil with one part potting mix. I know for many plants garden soil is a no-no because it retains too much moisture. In any case, my fire magic is nearly bare of foliage, neon splendor, while blooming (disappointingly), has lost it's share of leaves, and Thomas Edison, late to come up, is yellowing some. I really don't know what I'm dealing with here....an aggressive fungus, too much rain. Plus, I feel uncertain as to when to water. At this point, though the surface is dry, the pot with a depth of 12" is still damp/moist about 4" down. I've grown one dahlia, Seattle, in a pot using just potting mix. I don't know if I was lucky or it's really easy, but its performance was absolutely terrific (from Walmart).
I'd be happy to post pics, but any initial reaction to this potting recipe? I've posted a question on container recipes before but the one response I got was much to complicated for a simpleton like me....about five or six different components mixed in separate stages with some of the ingredients overlapping....I just couldn't find some of the stuff or follow the directions.
Sorry to ramble.