Dahlias Did Not Grow Well Last Year.

Question

When we dug up found worms eating into tubers. How can we plant this year to avoid worms and other pests from damaging the tubers as they grow. Been growing Dahlias for years and no problem till 2022.

Answer 1

Since you have been growing dahlias for years, if they are grown in the same place, it is likely insect eggs overwintered in the soil or on dead foliage. Keeping the area clean of fallen debris will help. Also keep the area weed free. Lightly digging in the area will bring up any worms, such as cutworms, that are hiding in the soil. You can drop them in a bowl of soapy water as you see them.

Did you have any problems with cutworms cutting the stems of the foliage, then feeding on the fallen foliage? They are a common pest of dahlias, and also could be what was attacking the tubers. Slugs also will eat holes in tubers.

https://www.gardeningknowhow.com/plant-problems/pests/insects/get-rid-cutworms.htm

https://www.gardeningknowhow.com/ornamental/bulbs/dahlia/dahlia-pests-and-diseases.htm

https://www.gardeningknowhow.com/ornamental/bulbs/dahlia/bugs-on-dahlia-plants.htm