Hmm, zero drooping may be an impractical goal with VS. It is common for VS, Limelight, Phantom and other large panicles with large blooms to droop (at least some) by late summer after storms. Varieties with dense, heavy blooms suffer from this problem if they develop those large blooms on green, thin stems. The only practical solution is to use stakes or to slowly allow the stems to thicken and to turn woody as woody stems are much stronger than green, thin stems. So there is some improvement with age. Try limiting pruning cuts to around 1/3 of the stem length or less. Placing VS in between two other plants can also help. Not planting it in the middle of the landscape by itself can help some. Using lacier varieties with lacy and-or smaller blooms can help; examples: Pinky Winky or Pinky Winky Prime; Chantilly Lace, Brussels Lace, etc.. Compact panicle varieties like Tidbit, Bobo, etc. also tend to have fewer drooping stems. Consider shaking off the water from wet blooms quickly after rains too.

In preparation for winter, VS and other panicles typically just need water and mulch past the drip line. Water if dry at a depth of 4". Reduce the amount of water once the foliage drops but do not let the soil get bone dry at that depth. So, continue watering if dry and above freezing and the soil has not frozen. Stop watering once freezing temperatures arrive. If you live where there is heavy wet snow, consider deadheading as soon as it is dormant as opposed to deadheading in late winter or in spring in order to minimize bending or breaking of brittle stems.

I'll have to stake every branch. Each branch is totally doubled over from the weight of the blooms.

If they do not recover on their own and are/remain bent or broken then you may have to stake/prune most or all of them . Lassoing or deadheading them may be an alternative.

The really large flower heads are too heavy for the branches to remain upright, especially after it rains. If you prune them, you will have blooms on freshly grown branches which are even less likely to remain upright; the older woodier stems will be stronger.

You have a few options:

- Plant them where the draping form looks nice, such as at the top of a rock wall.

- Prune out all the lower branches so it has a multistemmed ”trunk” that it weeps down from.

- Early in the season, before the plant leafs out, push in a bunch of stiff stakes and zigzag twine between them, or fasten some 4”-opening mesh fencing to them so that it is horizontal at about 2/3 of the height of the plant. This will add support for the stems to help decrease flopping, and once the plant has leafed out the supports will be covered up.

- Replace your plant with one that has smaller or less dense flowerheads. My favorite is Quickfire which has the longest bloom time of any of my panicled hydrangeas (early July until frost) and doesn’t ever flop.