Will it be harmful or any way beneficial to throw some 10-10-10 fertilizer at the base of new planted vines?

Question

for example, climbing hydrangea?

btw, this is end of July.

why and how so?

Thanks for your answers!

Answer 1

I see you have your doubts and I know why.

You usually don’t want to encourage a spurt of vegetative growth late in the season. It may not have time to harden-off before frost and cold weather sets in - and will die-back during the winter anyway.

If it is water soluble, I would wait until early spring (but not before the last frost is due).

If it is timed released or something like bone-meal, blood-meal, fishmeal or compost, I would wait until fall after the climbing hydrangea has gone dormant. The soil will become enriched throughout the fall and winter - and the nutrients will be available the minute the hydrangea needs them, come spring.

Answer 2

It won't hurt them, but the old sovereign was organic 'blood, fish & bonemeal'.

I'm not sure why exactly, but many years ago my Dad and family used to grow grapes in a greenhouse.  The vine roots were outside, and the vine inside.  

Dad always used to say "When you plant a new vine, bury a dead pig, or better, a horse, under the root".  Of course, that was in the days when horses were kept as draught animals and often ended their years on the farm.