Are these Dahlias big enough to go out yet?

Nollie

These were planted in 3L pots, were 30cm high, but had their tips pinched out so now closer to 20cm. They have been hardened off first in a unheated poly, then outside. My risk of frost has passed (fingers crossed!). What do you think, should they be a lot bigger before I plant them out?

First time growing in pots, slightly concerned if I take them out the pots all the soil will fall off the tubers, or should it all hold together?

amancalledgeorge

I'd wait a bit longer, no rush. They will grow nicely for another month in those pots.

punkdoc

A lot depends on when you have your last frost.
To keep the soil on when planting, ensure the soil is well saturated.

AnniD

I would leave them a bit longer too. They look nice and healthy, and it would help to build the rootball up. 

Nollie

Ok, thanks! I will be patient and leave them a bit longer in the pots to develop more roots. I just wondered if they would romp away more in the ground, but roots aren’t showing at the bottom of the pots hence worried about them falling apart in my hands. Ever so slight last frost was about two weeks ago.

fidgetbones

Pinch  out the tops of each plant to make it bush. It will slow it down a bit now, but you get more flowers overall. Keep it in the pot until the roots fill the pot. Keep it frost free for another couple of weeks yet.  Keep newspaper or fleece to cover it if frost is forecast after you plant out.

Nollie

Thanks @fidgetbones, the pic shows them after pinching out, they were about 10cm higher before. I’m pretty confident I have seen the last of the frost, but who knows these days... My patience hat is back on! 

Obelixx

I've just been weeding round all the dahlias I left in the ground last autumn.  Definite signs of life in one whole clump and maybe a shoot in one more.  i'll give them a week or two more.  Meanwhile, I have some half-price sale tubers just starting in the PT.  All singles so good for pollinators.

Nollie

I left my Bishop of Llandaff in the ground last year, its just shooting now, so I’m pleased it survived!

BobFlannigon

The roots will be fine, don't worry about re-potting them because of that.

Do you actually need to move them out from wherever they're currently growing?  Personally I think it's too cold (even if there are no more frosts), I would advise keeping them as warm as you can for as long as you can, they'll perform better (perform sooner may be more accurate).

Mine go outside just as they're about to start flowering, usually mid-June, if that means working around a tonne of pots, so be it.  Dahlias left in the ground are unlikely to start flowering until August, I don't think yours are big enough to do much else.

Nollie

Hi @BobFlannigon, 

I was going to plant them out, not repot, but following previous advice, and now yours, not yet! My poly is getting a bit crowded (they are still getting put back in at night, but brought out during the day to enjoy the warm sunshine). I need to make room soon to pot on tomatoes and some other perennials, but I will just have to squeeze everything in.

I am a bit ahead here, weather-wise. Last year, my new Bishop of Llandalf tuber, planted straight in the ground, was flowering by 13th July...