Hi Jeanie,
to All Things Plants!
What area of the country/world do you live? I'm in Florida and have been known to plant trees even in the heat of summer which works well as long as the plants get sufficient water but some trees are best planted in fall or spring. If you can give a little more information about the area you live I'm sure someone will be able to offer advice on the best time to plant your new trees!
Again, Welcome! I hope you find time to pop into a few of the forums that you find of interest and introduce yourself!
Lin