they are probably needing more water and fertilizer, unless your soil is holding water,then they probably need less water. Usually in TN by this time of the year its pretty dry though, so excessive water is most likely not the cause. Definitely not too late this year, you have until october to grow them.

OK, lets do a little math. Let's say you have a one gallon emitter on each plant. You're watering 90 minutes, 3 times a day. That's 4.5 gallons each time you apply water (assuming you don't have clogged emitters). A three foot shrub needs about 8 gallons of water each time its' applied. Visualize that one gallon of water will moisten one cubic foot of soil. 8 gallons would moisten an area 2' x 2' by 2 feet deep. That's just about right for your plants now but as they grow they'll need more water. Watering deeply pushes any accululated salts below the root zone which can cause yellowing leaves. A better strategy for watering is to apply the water once a day rather than 3 times a day. Allowing the soil to dry a bit helps oxygen return to the soil - roots need oxygen in order to absorb nutrients from the soil. Every three days this time of year is probably OK for your hibiscus. Desert adapted plants can get by with once a week watering. Instead of rock mulch, have you considered using a 3 inch layer of organic mulch? It does several things. 1) slows evaporation; 2) keeps soil cooler; 3) releases nutrients back into the soil; 4) reduces reflected heat and light on the plant. Hibiscus are acid-loving plants and they struggle here in our salty soils. Once a week or so use a teaspoon of white vinegar in a gallon of water and apply it to your hibiscus. This will help neutralize the soil a bit and make your plants happy. Good luck.

Kristopher, This is not a recommended method for some hibiscus. I would not recommend 'Bare Rooting' Hibiscus, unless they are a very robust CV. Erin Rachel is, and will recover over time. I was forced to do this with my Red Riding Hood, and it took several months to recover. I would cut the feedings and let the roots establish. Warm early morning direct sun will help. I have attached a photo of RRH currently after a bare rooting and a branch pruning. Remember that H R-S like TLC and slow changes. Hope this helps, Ed

I'm new to hibiscus (that's why I stopped in) but it sounds like your plant may be starving... Have you fertilized it - properly for the type of plant it is? Hibiscus are apparently a little fussy about what kind of fertilizer they want. I found some great care info at the website linked below. The nursery is for exotics, but if it works for an exotic, it should be great for a plain jane hardy hibiscus, IMO... Good Luck! Wren Here is a link that might be useful: Hidden Valley Hibiscus