Try feeding them weekly with diluted tomato food. This, like Miraclegro, is geared to flower production.

I find the slow release pellets dont do much for flowers. I feed with Miracle-gro every 1-2 weeks and water every day. If I run out I use Tomato feed.

I get tomato food because it's cheaper - and I use a lot of it. :-)))

Do you think it is just as good then Spritz?

Yes, I believe it has the same balance of nutrients.

Your baskets sound fine to me Muddyshoes :) The feeding pellets are encouraging healthy root growth and foliage, and you don't need to add any extra feed at this point. Later on in the summer you may need to supplement the feeding regime with tomato food....until then, all your plants need are light, warmth and water....and a bit of patience :) Don't worry, they'll burst into flower very soon:)

Thanks Spritz, I will use it more as I always have it. I so disagree with you Puddleduck if you want flowers in baskets/containers they have to be fed, which as the questioner says is what he wants.