Plant propagation deserves its props


It’s that time of year when plants begin to go dormant. Some gardeners want to save every plant in the yard, but that isn’t practical or possible. Instead of digging up every plant and moving them inside for the winter, consider taking cuttings or saving seeds. Starting new plants from existing plants is a great way to stretch plant-buying dollars.

Plant propagation can be achieved by a variety of methods. Save seeds, take cuttings, divide existing plants or try layering or grafting.

As plants end their growing season, they often have ripe, viable seeds that can be harvested. All plants that produce seeds can be grown from seeds, but some seeds are easier to germinate than others. Some seeds have longer dormancies, and some seeds have hard outer seed coats requiring scarification. And some seeds need to go through a moist, cool storage period called stratification before they will germinate.

Most native woody plants in our climate would naturally receive cool, moist conditions in winter months outdoors. Stratification is easily mirrored at home by storing seeds in a plastic bag with moist potting soil in the refrigerator. In Arkansas, they would normally receive cool, moist conditions for roughly three months, so do the same. One of the easiest seeds to start with is dogwood. Harvest seeds before the birds and squirrels get to them. When fruits turn red, seeds should be ready. Harvest fruits, remove the red outer pulp, and place cleaned seeds in a plastic bag with fresh potting soil that is moist, but not wet. Label the plastic bag, and place it in the refrigerator for the winter. In the spring, pot or plant seeds in the ground, and they should grow.

Growing plants from seeds — as shown here with a Southern magnolia seed pod — is one method of plant propagation.

Some seeds have hard outer seed coats that need help in germinating. They need to go through scarification. Home gardeners can physically scar seeds by lightly cracking seeds with a small hammer or abrading them with sandpaper or a file. Magnolia seeds, for example, are hard and impervious. Not only do they require scarification, but then stratification before they will germinate. Harvest seeds now, and remove the outer red pulp. Hold seeds between two pieces of sandpaper and rub them, or use a tack hammer and lightly crack them. Place seeds in a plastic bag with moist potting soil, and refrigerate just like dogwood seeds.

Many of our summer annuals have seeds that will germinate if the soil is warm and moist. Growing woody plants from seeds takes patience. While you can grow a camellia or wisteria from seed, it can take five to eight years before the plant blooms. Also, many plants do not breed true from seed.

If you want an exact replica of a plant, propagate plants vegetatively, using cuttings, division or layering of the mother plant. When taking cuttings, timing is important for some plants, while others can be rooted year-round. Normally a cutting should be no larger than 3 to 4 inches in length. The woodier a cutting, the longer it will take to root. Many woody plants are easier to propagate from softwood cuttings taken in late June or early July. They have gotten some strength in new stems but haven’t gotten totally woody yet. Rooting hormones are readily available at garden centers and can be helpful. Soil needs to be kept moist during rooting, but not saturated. To aid in controlling moisture and humidity levels, consider placing pots and cuttings inside clear plastic bags — basically creating a mini greenhouse. Check cuttings after 4-6 weeks by lightly tugging on them. If they don’t pop right out of the soil, rooting has begun. Once new growth begins, consider repotting cuttings into individual containers until you can plant them outside. If cuttings have not started rooting, seal them, and wait another 4-6 weeks. While many gardeners like to root their plants in water so they can see what is happening, roots produced in water are not as strong as roots produced in soil.

Plant propagation is not just for filling up your own yard, it’s a great way to share your plants with neighbors and sow the seeds of friendship.