Preserved tree limbs add a sculptural touch to your home's decor. They work equally well in flower arrangements and alone, whether displayed in a container or hung artfully on a wall. Homemade preservatives and do-it-yourself preservation processes extend the useful life of your limbs by keeping the wood and foliage from rotting.
Purdue University's Department of Horticulture recommends diluted glycerin as the best method for preserving branches with leaves. The limbs drink in the glycerin and distribute it throughout the inner structures of the branches and foliage. The university recommends using one part glycerin to two parts water. Although the glycerin adds a brownish hue that darkens the foliage, it preserves most of the color and helps the limbs and foliage retain their suppleness and pliability. Scrape the bark off the bottom few inches of the branches, then stand them in a container filled with several inches of the glycerin solution. You may need to add more solution as it is drawn into the limbs. Preservation is complete when the limbs stop taking in the solution.
Borax is a desiccant that absorbs the moisture it leeches from your branches. It can crush and bleach leaves and blossoms, however, so use it on bare limbs that have no foliage. Pour ½ inch of borax in the bottom of a container large enough to hold the tree limbs without overlapping. Lay the limbs in the borax, then add additional borax to cover. If you can't arrange the limbs side by side without overlapping, stack them between layers of borax. Drying time depends on the size of the limbs, but it could be several weeks.
Mix borax with other desiccants to make preservatives that are gentler on leaves and blossoms than straight borax, but still dry the limbs relatively quickly. Cornmeal and fine sand both work well mixed with borax in ratios ranging from 1:3 to 1:1. Borax is heavy, so use lighter concentrations for more delicate limbs and limbs with fragile foliage, or mix the borax with cornmeal rather than sand. Adding up to 3 tablespoons of salt per quart of borax mixture speeds the drying process
Alternatives to Borax
Sand or cornmeal can be used alone for slow drying. The University of Florida Cooperative Extension notes that cat litter, corn starch, powdered detergent and dry sawdust work, too. However, Purdue University's Department of Agriculture considers these materials to be less reliable.
Sturdy limbs without foliage may be preserved with air drying. Just bundle them loosely with string and hang them upside down in a cool, dry place for several weeks. They need plenty of air circulation to dry properly. Safety dictates that you allow them to dry naturally, away from direct heat.