[AndyRVTR]

Hi all, Mrs R bought a thornless blackberry plant earlier in the year and I've been helping it along by training the runners along wires but I really don't have a clue what to do with it. Anyone any ideas about what to do please?

[mumofstig]

On mine I cut out the old brown/woody stems and tie the new green ones along the wires, pruned mine a little while ago.

[Aunt Sally]

John has some advice:
https://www.allotment-garden.org/fruit/blackberries-growing/

The RHS has good advice too:
https://www.rhs.org.uk/fruit/blackberries-and-hybrid-berries/grow-your-own#

[AndyRVTR]

Thanks Aunty... John says "An easy method of training the fruit is a sort of alternating cordon method; train this years’ canes to one side, the next year’s growth on the other side. After fruiting, the first side is cut off at ground level. In this way the fruiting side alternates each year".

As our runners have been trained both sides, do I cut back to the main stem leaving thecmain stem in place or do I cut the whole plant down to ground level?

[New shoot]

I would cut the main stem down rather than remove it completely.  You can go one side and then the other and that does make things very simple.  Those newer canes will still be flexible enough to untie and move across.  You need to cut the lead cane back though, to make it throw new canes at the base next year.

I have several large hybrid berries growing on wires and tie it new canes on both sides.  It is pretty easy in future years to see what is old growth, as that has fruited and the wood is darker and thicker.  You will get newer growth springing up and rather than tie it it, you can peg or clip it to the wires out of your way.  The trick is to use a different fixing method than the stuff you ties in the previous year.

Pruning is then :
-unpeg or clip the new stuff and lay it down on the ground
-prune the old stuff at the base then untie and remove it it so you know what it what
-lift up and tie in the new canes