Penstemon cuttings

I took some penstemon cuttings earlier in the year, and placed in the propogator...these died. Took some about a month ago, non flowering shoots..cut below a leaf node, some I dipped in rooting powder, some I did not. I left half of each of those on the windowsill, the other half in my unheated greenhouse. Most have died...one or two are still green but have wilted.

Can anyone shed any light on what I might be doing wrong?

Also, the donor plant is still in the bed...what if anything can I do to protect it from winter? Cut it down and cover rootstock with compost, leave topgrowth on or simply dig up, pot on and overwinter in the greenhouse?

BTW, I have googled this already and following advice found there is how I took cuttings twice this year that are now gone.

Many thanks!

Steve...

 

Hi Steve
Have you tried the search, 3rd button from the right under your name ,theres some good info there.Type Penstemon.
I have some tiny plants i grew from seed this year so i was looking to find out how to care for them in the winter aswell.
It says not to cut them down as this will give them a little protection throug the winter

 

Steve I have never taken Penstemon cuttings - so have no direct experience. Although you have reminded me - that I meant to do some this autumn. So I will have a go.

There is some debate on the subject here. http://www.gardenbanter.co.uk/archive/index.php/t-38218.html

Generally plants root quite happily by themselves, so you don't have to make them do anything to make them root, but you do have to stop them dying before they have rooted. Cutting material initially doesn't have any roots so cannot draw up water from the soil, but it is loosing moisture from the leaves. So its a race - can it grow roots before it dies of dehydration or dies from rot from too much moisture in the soil.

Usually the key is to stop the plant loosing moisture whilst it prepares to grow roots. So to prevent moisture loss - keep it out of the sun, don't have too many leaves, mist the leaves to give it a drink but don't water the soil after the initial watering, or the stem will rot. And you can cover it with a polythene bag (with some air holes) to keep the moisture in. I also like to use a heated propagator for all my cuttings as the extra warmth speeds up the process. But a heated propagator is often not neccessary.

On the question of overwintering plants - they don't like the wet. So if in doubt lift it and put in in a greenhouse to keep it dry - it obviously need a bit of water.

 

Having a new garden I've been eager to take as many cuttings as possible - penstemon included.

Although it is probably a bit late in the year, I've just taken a few more and don't expect to have any more difficulty with those than I've had with any of the others, although they will of course take longer to root because of the shorter, colder days.

I do pretty much as Marley has described. I take a non-flowering shoot about 3" long, cut it just below a leaf joint with a sharp (preferably sterile) knife, remove the lower leaves, dip it in some hormone rooting powder or liquid and stick 3 or 4 around the edge of a 5" pot of compost - I usually use JI Seed or JI No.1 mixed 50/50 with perlite or vermiculite, water them in and cover with a polythene/freezer bag (I usually stand them in a shallow tray on some LECA, just to keep them moist) then do nothing until you see tiny white roots peeping out of the bottom of the pot at which point I pot them up individually.

Don't cut down your parent plants, most penstemons are hardy (although they may suffer a bit of damage) but the stems are hollow and the old foliage, flower heads etc., will help protect the plant during the winter - stop it from rotting from the inside. Cut back the 'dead stuff' next Spring when you see new growth appearing.

 

Many thanks for all the detailed replies, think I'll try taking a couple more cuttings today..nothing to lose and everything to gain.

Great idea Marley to use the plastic glasses to enable root formation checking!

Thanks for the link Peter.

Steve...