I only fertilize once a season......in spring, after any pruning, when I see new growth forming. Since most of my clems are in containers, I use Osmocote, which lasts the entire season but any inground clems will get an organic veg fertilizer or just a good dressing with compost, again just once early in the season. Now and again I will fertilize during the growing season with a liquid solution I use with all my other plants in containers but nothing very scheduled or regular. And I pay no attention to whether the vine is in flower or not.......I have not found that to be an issue.

FWIW, no plant established in the ground needs to be fertilized on a monthly basis!! With average soil conditions, they should be getting the majority of what they need nutrient-wise from the soil and the fertilizer is just to supplement what nutrients might be low in the soil.

I have grown a lot of clematis in my day and even worked for awhile for a wholesale grower and have never fertilized any on a monthly basis. They just don't need that much fussing :-))

Thanks, gg! I use Rose-tone, and I'm pretty sure the soil is good where they're at. Saying that, should I go ahead and skip fertilizing until later in the summer or if it seems they need a helping hand at another time?

I thought about growing a clematis in a container, if I find one I might buy it.

If using the Rose Tone, I'd go ahead and do it now :-) Organics take time....weeks to months...before the nutrients are broken down into plant usable forms that the plant can absorb. Or you can skip if you prefer - I have often gone a season without fertilizing with no ill effects - or maybe just do a liquid supplement later if you think they need it.

I'm going to fertilize this morning. I got everything watered last night so they're ready to go! Thanks!