Question
Some of the leaves on my dahlia are curling and I can't see  any insects causing this.The leaves look healthy and green. Looking forward to your answer, thank you .

Answer
Doris

Iam sorry for the plant decline you are experiencing.  

There may be 1 of three things happening with your plant.

1st.  Overwatering - Check your soil for excessive moisture.  
2nd. You may have some unwanted guests eating away at your root system commonly referred to as Nematodes.

3rd. You may have sprayed this plant recently with a new sprayer that may have had some residue in it from another chemical.

There is a new product on the market that is Non-Toxic and all natural.  It cleanses the leaves and raises the plants ability to make sugars from light and co2.  It will enable you plants to defend agianst future attacks and re-establish a waxy cuticle layer for protection and gloss.

Crowley's nursery [email protected] in Sarasota Florida carries it and its name is Atomic Growtm.  This product will repair and replenish your plants ability to defend itself agianst bacteria and insect both above and below the ground.

Hope this helps you.

Jim Shellenback