Topic: Tatty Dahlias.

[Garden Manager]

As with most things in the garden this summer several of my dahlia plants have suffered extensive slug/snail damage, and a couple have been turned to lacework by the little critters. The plants are trying to flower but they look so pathetic and spoil an otherwise good looking border.

I was wondering if it was worth cutting them back down to ground level, giving them a feed and starting again, this time with protection? Will this work or will it make the plants go prematurely dormant (like hostas seem to do if cut back)?

Please advise.

[Heldi]

I'm no dahlia expert by a long stretch but I thought I'd let you know that in the past I've had dahlias damaged by wind and rain where they have actually snapped right off at ground level. They did grow back and I did get quite a good show a bit later in the summer.

I've deliberately given them a "tidy" up too having noticed new buds forming further down.

Have you had a look right down to the base of the plant to see if there are any new shoots that you could rescue with some slug protection whilst removing the already nibbled parts?

Just had a thought,it also may depend on what type of dahlias you've got. Some of them are quite different aren't they? Mine are mostly the big blousie kind..okay the vulgar kind then!

I usually put porridge oats around the base of mine when the shoots are just showing. Seems to help to deter the slugs for a bit ,until the blackbirds nick it all!

I love dahlias. I hope you do eventually get a good show.

[petengade]

Mine were similar to yours (badly bitten) just gave the slugs and snails their blue lunch and plants have all recovered, no cutting back was needed.

[Garden Manager]

Just an update: My attempt to rescue my dahlias have failed. Oh they started to regrow OK, but this just gave the slime army a tasty treat and the plants were back to stumps in no time. Worse a few of the damaged plants have since died back.

I am now not sure what to do. I had feared the tubers had rotted in all the wet weather but I had a 'rummage' around and the tubers seem firm. I dont know whether to lift the tubers and put something else in the gaps (I have unsightly large holes in my borders where the dahlias should be), or try and revive the dahlias. I hav put slug protection and cloches over a couple in the hope I can 'force' the plants back to life. Would this work or have the tubers now gone prematurely dormant and will not grow again this year?

Please advise

[silverbirch]

I've never known a dahlia to go in to early dormancy, and it's a fairly standard exhibitors trick to cut them back hard if they get away too quickly so you can show on the second growth.  I'd stick with it.  If you lift them now there is a chance the tubers won't bulk up enough to get them over the winter.