There is nothing wrong with cleaning the tubers. It is often easier to see the eyes for new sprouts when washed. Here in Canada many of us do this every fall. We then let them dry TO THE TOUCH, but not too long, and then dip them in a fungicide or bulb powder to combat fungus, and put them away for the winter.

I would not be using a space heater as that may dry them out too much. It is hard to say whether you should plant right away or not. Is all danger of frost past? If so, plant. If not, let them rest in a cool spot.

I have had glads and dahlias in close proximity with no ill effect.

Hopefully someone else with differing or similar experience will add some comments as well.

i'm in the west sonoma county area (70 miles north of san francisco and 15 miles inland from the coast). while we did have a couple of weeks of unusually cold weather recently, i'm pretty confident that we're past any freeze danger. thanks for the response. - bob

The reason not to grow dahlias & glads together has to do with the fact that glads get thrips easily & can pass them on to the dahlias.

Hmm, had never heard of any reason to not plant dahlias near glads. But the thrips idea might be a reason.

In California I would suspect a dahlia can stay in the ground year round. As pointed out, up here in the north zones, dahlia has to be removed AFTER a hard frost and overwintered in a COOL place...after letting them dry for a day or so in the warm sunshine.

For that reason, I avoid purposely wetting the clump further.
The soil can be flicked off with fingers and put somehwere to dry.
Further washing wont hurt the clump....just prolongs the drying. For that reason then, I would suggest NOT using artificial means of drying. Let the sun do it by placing them in a place where the sun maybe is not beating down on them...let them dry more naturally.

The 'eyes' will be more obvious tho as the plant is cleaned...but I still woundn't heavy wash them.
Dampness breeds mildew; so that is cause enough to avoid it.

The reason it is recommended that dahlias not be planted where gladiolus had been previously is because gladiolus corms may harber botrytis. This is particularly the case in wet weather. It really has nothing to do with insect infestation. A good insecticide program can control insects. Fungi disease such as botrytis is an issue entirely separate from insect infestation.

That's strange, Flowerfarmer- our Ag. agent told us if we grew Glads on our farm anywhere, we couldn't get the phytosanitory certificates to ship all over the world because they couldn't certify that there weren't thrips present. So.. we don't grow glads & we do get certified every year.

You most certainly can rinse the dahlia tubers and let them dry naturally. It will not harm them, just make sure they are dry when you put them away to avoid mould and fungus problems. No space heaters are necessary or recommended. Some people like to dust the tubers with a fungicide.

Gladioli should not be planted near sweet peas, either; thrips and aphis being the main troubles!