On a side note, I also have a limelight in full sun and it is also thriving. Although, there are 3 burnt leaf's, but I stopped watering it for a few days because I noticed I was overwatering it (it is in a bed that does not have drip) so I think my horrible watering skills play part in the burnt leaves.

Kyla, I don’t cover any of the types of plants you mention, and I rarely cover anything. When we talk about ‘tender’ plants, it would be things that are very sensitive to frost. So think annuals, not usually shrubs and perennials. If they are hardy here, they are used to this weather, which is typical for this time of year. The one exception on your list might be hydrangeas, but not Bobo. It is Hydrangea paniculata and perfectly hardy here. If you have other hydrangeas of the macrophylla type, you might cover those to protect flower buds. And when you cover things, you can use any of those things you listed. Cover at night, and remove first thing in the morning.

Great plant choice! It looks like the brown stem parts are last year’s growth and the green branches are this year’s stems. As far as the brown spots on the leaves, they could be a slight fungal infection from overhead watering either in your garden or previously at the nursery or more probably mechanical damage that happened when moving it to your house and then planting it. The lack of perkiness is that it is a new planting and the plant is still settling in and growing new roots, so it is a bit stressed, especially with the recent hot weather in many parts of the US. If it needs it, give it some temporary shade on hot days, such as a lawn chair placed to the SW of the plant where its shadow will reduce light levels during the hottest part of the day. Keep an eye on soil moisture, letting it get to just lightly moist before giving it a long slow deep watering that soaks the soil to 8” or more. If the limp branches don’t perk up overnight, then come back and let us know, but that isn’t unusual to see in a first year planting in hot weather.

New hydrangeas are normally kept in part shade and coddled considerably by the wholesaler and the local plant nurseries. When brought outside and planted in full sun in the middle of summer, the blooms may brown out early until the plant becomes established in the garden and develops a large root system. Normally though, the blooms will go through a series of color changes and if you observe that they are turning brown "early", I would start to monitor the amount of sunlight and the amount of water that they receive. In their first year, I have been known to provide temporary shade in the form of outside chairs and even built some cardboard contraptions. To monitor the water, insert a finger into the soil to a depth of 4" and water if the soil feels dry or almost dry. The amount of water used should be enough to get the soil moist down to a depth of 8". Use 2-4" of organic mulch at all times of the year. The spent blooms can be deadhead now or you can keep them for winter interest. Otherwise, the plant looks fine. The other plant that you have may be older, may have more shade or may have a larger root system. In the extreme south, paniculatas like Bobo tend to bloom just as temperatures spike to the 100's and that can brown out blooms too.