Hi Bob:

You live in the midst of a lot of specific Holly knowledge. Contact the Holly Society of America, and consider membership in this fantastic organization. Seek out members that live on Long Island with similar situations as yours (quite different than Michigan, or the UK, or Tennessee). There are outstanding members at places like Planting Fields who would be a great asset in your efforts.

Holly Society of America (hollysocam.org)

Practices in planting in other places may be similar, but your site requires attention different than those mentioned. Your temperatures, moisture regime, WIND, potential exposure to salt spray - all are very different than fellow participants here. Fortunately, what I know of Long Island is that it generally is a great place to garden.

Show us some pictures of your plants! "Holly bushes" is a generic term, but I'm interested in whether these are actually trees (Ilex opaca - American Holly) or one of the many species of holly that are actually shrubs.

I will echo guidance here that you should plant at the proper elevation (root flare at the surface) in your native soils, and apply all organic matter, amendments, and fertilization to the surface of your growing site. As your plants settle into their new home, the plants will tell you which parts that they have no longer chosen to support, and where they are going to invest energy. As branches die, then prune them off.

Shading and wind protection are good efforts in establishing broadleaf evergreens like many Ilex species. And your watering needs to focus on the rootball of the transplanted hollies - as that is the only place that they have roots! Don't let that area dry out. Drip hose/drip irrigation is a good investment for this application.

I have had more than a bit of experience with transplanting larger hollies.

Here is a nice array of "holly bushes" - actually 30 or so named selections of American Holly - that we planted in 2013 at Central Park in Louisville KY to screen out the ugly stone building (!) across the street.

While I would rather have had larger rootballs on these nursery-grown trees which would have brought more roots to the landscape, this is a rough standard rootball size for the height/age of these trees in this part of the country.

No soil amendment was done. This site formerly housed a bunch of Austrian Pines planted in 1993 before my employment. Those trees declined from the day they were installed (Pinus nigra is not a good long term species for Kentucky conditions), and were grubbed out in advance of the holly installation. The bed also had vinca/ivy mixed as groundcover. A heavy application of chipped hardwood mulch is the only amendment since added.

Water, water, water - and today there are very happily growing American Hollies filling in, with only a couple of casualties that aren't missed. While shading may have benefitted these plants, it was not a practicable choice in a public park - nor for our Victorian neighbors...

Thanks so much @ViburnumValley central KY Bluegrass z6 for this information! I've posted pics below. I think I might have more than one variety, as some are a slightly different shade of green. For reference, that first bush is about 65" across. The others are the same or slightly smaller.

I know the challenges come with the hot weather, but so far, 19 days later, they're mostly looking pretty good. We have been fortunate as the weather has been mostly on the cooler side. They've been getting watered daily. We just cut larger beds, and those will be mulched in the next day or two.

There are some signs of stress, and I'll go pruning this evening to remove the parts that, as you said, have not been chosen to be supported. One bush, the last one below, is especially challenged.

I work from home, so I can water them at will, whether it's one or more times per day. I'm committed to helping these bushes survive :-)

I do have some questions:

1. In the warmer weather I'm assuming it would be OK to water more than once per day to make sure there's no chance of that root area drying out? It's easier for me to do it manually since they're located in various places around our property.

2. When watering in the shade, is it helpful to water the leaves too? It seems to make sense as it would help them with moisture, but I don't know whether they are prone to fungus.

3. And when watering in the sun, is it at all helpful to spray the inside of the bush/leaves, to help with moisture. (Shower setting from inside the bush, not allowing it to get on the leaves in the sun.)

4. If covering the plants could be beneficial, do you have any recommendations on a specific bush cover/bag? The ones I've found seem to mostly say they're for winter protection.

The hollies you planted are beautiful. I've got one gorgeous one that I planted outside my office window a few years ago. It's about 8 feet tall and is glowingly healthy! Here's a pic below.

Thanks again for the comments!