Sorry for the delay getting back. I have a vacation condo in Rockport so we have been dealing with hurricane debris and salvage. The initial problem was improper watering. When roots get a fungus and rot away, the plant above dries out making it look like it is not getting enough water. Truth is the plant is not getting enough water, but the cause was too much water. Watering dead roots doesn't fix it. At this point you have to hope some of the roots were not completely dead and will return once things dry out. Adding fertilizer stressed the situation rather than fixing the situation. Of course watering after the fertilizer was necessary to dilute the fertilizer, but the yard already had too much water. What I would do is to buy a bag of ordinary corn meal at your local feed store (call around for availability). Scatter that at 20 pounds per 1,000 square feet. And don't water it in. If the soil has already dried out and the corn meal does not start to look gray in a couple of days (a good sigh of decomposition), then lightly spray over it with a hand held spray nozzle. All you need to do is moisten the corn meal. Corn meal will help feed the soil microbes and, hopefully, kill the disease microbes causing the roots to rot. If you don't see any green up after 3 weeks, then the lawn is likely dead. I would not water it again for at least a month to be sure the soil is drying out. Here is some information about deep and infrequent watering. Watering: Deep and infrequent is the mantra for watering. This is for all turf grass all over the place. Deep means 1 inch all at one time. Put some cat food or tuna cans around the yard, and time how long it takes your sprinkler(s) to fill all the cans. Memorize that time. That will be the time you water from now on. My hose, sprinkler and water pressure takes 8 full hours to fill the cans. Your time will likely be less. I like gentle watering. As for watering frequency, that depends on the daytime air temperature. With temps in the 90s, deep water once per week. With temps in the 80s, deep water once every 2 weeks. With temps in the 70s, deep water once every 3 weeks. With temps below 70, deep water once a month. Note that you have to keep up with quickly changing temps in the spring and fall. This deep and infrequent schedule works in Phoenix and in Vermont, so it should work for you. The reason for deep and infrequent is to grow deeper, more drought resistant roots and to allow the soil to dry completely at the surface for several days before watering again. If it rains, reset your calendar to account for the rainfall. That is what you should have been doing instead of watering every other day. In Houston while the climate is unbearable in the summer, the problem is humidity and not the actual heat. Humidity keeps the water from evaporating, so rather than watering once a week, you might be able to water deeply once every 10-14 days in the summer.

I'm with Sheila; using those two chemicals is overkill. The main thing newly planted roses need is regular watering and time to make root growth before any fertilizer is applied. KnockOuts are really tough so I suspect something more is going on here. There may be air pockets around the roots, which prevents the roses from taking up water. Check the ground around the base of the roses by pressing down with your feet to ensure the soil has been firmed around the roots. Then apply water and observe closely; if bubbles appear on the surface you have have air pockets. When planting, it's a good idea to fill the planting hole just halfway with soil, then water until bubbles no longer appear, then fill the hole up the rest of the way and water again.

Wow you have run the full cycle with your plant. I don't have much advice other than check for more bugs and give it some time to adjust perhaps. I have a Chinese mandarin that I started from seed and I bring it inside in early fall before night temps get below 15 degrees or so. It lost quite a few leaves after bringing it inside this fall. I use mostly peat and about a quarter of garden soil, that has been working well. No bugs so far. I have been using rose fertilizer that has micro nutrients and flush every second time. I haven't used grow lights yet but will have to if I want fruit. best of luck with your plant.

It's worth a try as long as you water it in correctly until it roots, and then feed it correctly once it's in (on Memorial Day...er, end of May as that's an American holiday!, the first of September, and around a month before ground freeze...hopefully October 1 for you folks). Use any good high-nitrogen fertilizer.