Yes, you're right! Major transplant stress! All you can do at this point is keep it well watered and hope for the best.

I understand that sometimes need overrules proper timing but this switching containers should have been done while the plant was still dormant (late fall or winter), not now when it looks to be pretty much fully leafed out. And it is very difficult to downsize container plantings - typically you go up in size, never down. Downsizing just results in a lot of root disruption that a plant during the active growing season has a very hard time adjusting to. And it shouldn't be sharing space with the camellia. These are both decent sized shrubs that each need their own appropriately sized container.

I also saw your rhody post. Rhodies can be cut back hard. That will help with legginess but it's going to take a couple of years before the plant looks decent. Let me just offer this thought.......in their current state, these plants all look pretty bad (and that's putting it mildly). Probably not the best image to portray in a public courtyard with folks coming and going, where you want plants to look lush and well groomed. I would suggest you give these plants to someone with a garden with room to care for stressed and unattractive plants outside of such a visible, public space. Then replace them with some healthy, new plants in good condition.

It is also important to know that plants grown in containers need much more care and attention than do those same plants growing in the ground. You need to size the containers appropriately, use the right potting mix, provide adequate water and frequent fertilization and finally, realize that they will need to be removed from the containers periodically, root pruned, the soil refreshed and the plant repotted. You can't neglect container plantings and expect them to thrive or look good indefinitely - you can see for yourself the results.

You need to get another pot for the hydrangea. The hydrangea and camellia can't coexist in that pot. I suggest cutting the hydrangea back to the ground. Maybe leave a leaf or two. Dig it out and put in a new pot. Keep the soil moist until it grows new leafs. You won't get any blooms this year, but it gives the plant the best hope of survival long term.

I would take the plant - pot and all and sink it into a bucket of water. You could also take it out of the pot and just dunk it up to the middle of the bush - and leave it in the shade for a couple of days. It will probably come back. The other trick - learn from a florist - is to cover the entire plant with water. Sounds weird, but what have you got to lose. I think you will be surprised at how it will rehydrate. This is done in floral shops to rehydrate cut flowers. Once the leaves start to plump up, cut the branches half way down and put back in some wet good potting soil. All of the leaves may fall off - but don't lose hope! lol Worst case - cut the branches, to two or three leaf nodes, put one node in the soil, and the other one or two up, water well and they should root into new plants. It will take several weeks for them to show roots, but be patient. Repot when lots of roots and keep in the shade and you will have enough hydrangeas for all your friends.

Before we get all crazy with the water, hydrangeas can be overwatered very easily. Looking like the above can also easily be a symptom of overwatering. Keep in a pot in an area with no direct sunlight in moist soil only (like a fresh bag of soil with a quart of water to start). Pat down the root ball so there are no air pockets in the soil. Otherwise, it's okay to loose some roots in the transplant process - often they travel a couple feet away to find additional moisture and nutrients when in-ground.