1: Because the plants grow at different rates and have different leaf sizes, some faster growing plants in mixed kits could over-shadow and block the light from slower growing plants. Experienced gardeners will know how to avoid this
issue.
2: Our nutrients have been specially designed for the group of plants in each kit. If kits are mixed the plants could be under or over-fed, resulting in less than optimal growth.
3: Your AeroGarden comes with pre-set light cycles according to kit type. If you mix kits you could be sub-optimizing your plant's growth by giving it too much, or too little, light.