Profusion Crab Apple trees
I recently purchased 2 Profusion crabapple trees. Both have been stored behind my house and receive 6+ hours of sun as required. I water them periodically with the garden hose until I can plant them. I have noticed that the leaves have begun to change colors. Do they have a disease or is it too much water ?
Early coloration and scorch are signs of stress. In this case likely too much sun and not enough water. In the nursery, they would likely be watered every day. They could be pot bound as well and those black pots also get pretty hot in that much sun.
Move them to a more shaded area and keep them well watered.
It's too hot right now to plant them unless you can carefully monitor them.
Wait until cooler weather to plant.
Be sure to check for circling roots straighten them and loosen roots if potbound.
Take a look at our photo gallery of environmental problems including tabs for girdling roots and early fall coloration here:
You can use this link to find helpful information about planting and caring for new trees: http://extension.umd.edu/hgic/plants/trees-shrubs