Growing Sweet Gum (Liquidambar) from Seed: Collection, Stratification, and Care

Sweet gum trees can be grown from seed, but they require patience—germination may take up to two years. The reward is a beautiful, resin-producing native tree with stunning fall color.

Seed Collection and Preparation

1. Collect mature spiky seed balls in fall.
2. Place in a warm, dry spot on paper. As they open, shake out seeds.
3. Sow immediately in a mix of 1/3 coarse sand, 1/3 compost, 1/3 peat moss.

Stratification and Germination

Sweet gum seeds need cold stratification. Plant in a deep tray (8"), cover with 1/6" of mix, and place in a cold frame or unheated garage over winter. Keep moist. Germination is erratic—some may sprout in spring, others the following year.

Seedling Care

• Transplant at 4" height to individual pots.
• Keep in cold frame for first winter.
• Plant in final location when 1-2 ft tall. Minimize root disturbance—sweet gum dislikes transplanting.

Uses and Cautions

The resin (storax) has traditional uses for colds, sore throats, and as chewing gum. But the hard, spiky seed balls can puncture tires—avoid planting near driveways or walkways.

With time and care, seed-grown sweet gums become magnificent shade trees.