Hardiness Zone: 7a
Pat from Lubbock, TX
Sweet Gum trees are considered to have a medium to fast growth rate. A medium growth rate indicates a tree that has a vertical growth of between 13 to 24" per year. A vertical growth rate of 25" or more a year is considered fast. These rates represent ideal conditions, of course, and don't take into account numerous variables such as soil fertility, drainage, moisture availability, light exposure, etc. With a mature height of 60' to 75' and a canopy spread of 40' to 50', they provide wonderful shade and diverse fall colors.
Sweet Gum trees prefer full sun and moist soil conditions, although they are considered somewhat drought tolerant. They seem to tolerate a wide variety of soil conditions.
One thing you may want to consider with these trees is the fact that after the first 12 to 20 years, they start to flower and produce prickly round "gumballs". Many homeowners find the gumballs a messy (and dangerous) tripping hazard and a real nuisance to clean up. Others use the gumballs for craft projects or as mulch (animals, especially rabbits, don't like stepping on them). If you are planning on planting a Sweet Gum in a high traffic area, you may want to consider the sterile, fruit-less cultivar called Liquidambar styraciflua ('Rotundiloba'), otherwise the fruiting varieties are best located in an area of the yard where the gumballs won't pose a problem.
Ellen
This is a page about, "Do sweet gum trees weep sap?". Sweet gum trees do not weep sap, however the trees may have aphids and they can drip honeydew on you, your car, or patio.
Many yards contain sweet gum trees and they can have issues with pests and disease. This page contains advice about problems with a sweet gum tree.
