When to thin?

My centennial plants have 20-30 bines stared on each plant that are from 3-18 inches long, is it too soon to start cutting back the new shoots yet?

Id say no... I have been cutting mine back for a few weeks.

I now have three bines per plant that are about 18" tall... Id cut back the shorter ones so that the more aggressive bines continue to grow rapidly.

I struggled to find commercial information about this , so went with common sense.

Once you have 2-3 strong bines curling successfully up your rope/twine or trellis, then start to thin the others to put growth into the ones that have been chosen.

My Nugget and Cascades , have mostly been selected by now, others still waiting on seeing how well they do up the ropes.

If you break a tip off a bine it stops growing , so make sure the ones trained are going well before cutting back

If you have 2-3 bines long enough to wrap on the twine, do it and cut the rest. Every year mine seem to jump from 'did they survive?' to weed whacker time in a week.

anyone do a side-by-side comparison with thinned and un-thinned harvest size?

I'd think that un-thinned would be better for root development in younger plants than thinned ones would be.

Thinned, from what I have read and seen, is always better.

Young plants with poor root systems cannot support multiple bines. They also put too much energy into bine growth and this takes away from root growth. Meaning, there is a balance.

Established plants with good root systems can support a few bines, but too many and they overwhelm the ability of the roots to gather nutrients.

I cut back my bines 4 days ago... came home from a 3 day trip and the remaining bines great at least 6". My Cascades are almost 2' tall, the Mt Hood and Willamette are 18"

Thanks for the replies, I cut back about half of the small shoots today, I will let the rest grow till I can get the best ones to stay wrapped around my support string.

It's never too soon. As soon as you can tell which ones are the runts, pinching them off will pump a more energy into the others. I pinched a few of mine of today, but most aren't up high enough.

Tom

Thinning is the hardest thing for me to do to just about any plant... I just don't like to "limit" the plant, even though I know it's better for it... still I have to get out to mine and thin, I've just been avoiding it...