How to Fertilize your Dahlias

By The Colorado Dahlia Society

After your tubers are in the soil, they’ll need regular nutrition.

Colorado Dahlia Society members suggest using

  1. Osmocote
  2. Fish emulsion

Osmocote is a reliable favorite and should be applied once, as soon as your tubers are in the ground. Its time-release formula keeps nutrient levels consistently high for strong root and flower growth throughout the season.

Fish emulsion provides nitrogen and promotes healthy soil microbial activity. Just add it to your watering can every two weeks. Fish emulsion is safe to use around kids and pets, but some brands may smell more than others and even attract animals.

Swan Island Dahlias recommends using only low nitrogen fertilizers.

However, our members have found that strategic nitrogen applications can be successful in our growing environment.

Additional information:

fish osmocote