Are they all first year tubers? If they are, sometimes it takes another year for them to be up to full steam.

I don't feed my dahlias at all and have had good success. I would think you'd want a fertilizer with a low nitrogen content though.

Perhaps your dahlias are in too much shade. Shade reduces blooms.

(Amused sarcasm) Oh, yeah, those just look awful. I think you need to dig all those out and ship them to me. Here's my address.

:-)

Yeah, the shade could be an issue. Dahla really do flourish better with every extra ray of sunlight you can give them. My first year tubers performed amazingly...except the one that only gets sun from noon onward, which is a little weaker.

Feeding's fine. They're on the low side of average as far as demands go, but that's still in range of average. Mine get Miracle Gro (half rate) weekly, plus organic feeding (heavily) monthly--exactly like the rest of the garden including marigold, zinnia, and tons of salvia.

There is a technique called 'stopping' or 'topping' that growers do with dahlias that would help you in your shady area next year... You pinch out the top sprout after 3-4 sets of leaves form on your plant. This forces it to put energy into growing lateral branches, and will result in more flowers on a shorter plant.

In addition, I see that you are growing in pots. I have never had much success in pot growing with dahlias, as I am really bad at watering individual plants every day. They require more water then an in-ground dahlia, as the feeder roots can't reach down into the soil for extra moisture if it needs it. Lack of adequate watering might be why the pots further from your door seem to be smaller.

You might consider increasing your amount of fertilizer by feeding weekly, since the plants are confined to the soil you provided. The type of fertilizer isn't as important as the consistency and quantity. Nitrogen is not a bad thing, as long as you stop feeding late August, after the plants have gotten off to a good start.

Good luck!
CC

more sun, better drainage and low nitrogen are really helping this year, this is my fourth year growing them.

this one took three years to bloom.

steveg1