On Nov 17, 9:28*am, wrote:
In article ,

Bertie Doe wrote:
"Dave Hill" *wrote in message
....

/The main thing that kills dahlias left in the ground is the wet not so
/much the cold, though in a hard winter that will wipe them out.
/As you say Bob you have to put slug bait out from mid May onwards if
/you have left them in.
/Leaving dahlias tubers in plastic bags will almost certainly lead to
/rot unless they are 100% dry, store them in dry compost, slightly damp
/pearlite or vermiculite or peat.

I've noticed the plants don't seem to grow as tall as when I put them in,
say 5 years ago. I suspect the soil is exhausted, despite getting 3
wheelbarrows of cow manure in December.

Possible, but other likely causes are the poor summers we have had,
or parasite build-up (from nematodes to viruses).

Regards,
Nick.

If ytou havn't divided the tubers in 5 years I'm not supprised they
are not growing as tall as they first did.
First year you probably had 2 or 3 shoots, now you are probably having
getting on for 20..
If you think, with herbacious plants when you divide them you take off
younger growth on the outside and dump the Old middle,
With large clumps of dahlias split them, possibly using a spade to cut
them up if they are realy large, select the tubers with the younger
stems, you will find old and dead stems and tubers, dump them.