The yellow crabapple is a delightfully showy tree that will embellish the landscape almost year-round, starting with fragrant clusters of blooms in early spring, followed by colorful crabapples that will last from late summer through the end of January. The crabapples, which start out as a creamy yellow, will turn to a deep gold with a rosy blush, and will keep the wildlife happy during the cold winter months. Yellow crabapple trees are easy to start by taking a softwood cutting in early summer.
Choose a few stems from a healthy yellow crabapple tree. Stems are just right for cutting if they bend easily and break with a popping sound. If the stems are too flexible to break, they are too immature. If they're too tough to bend, they're too old.
Make a cutting about an inch blow a leaf node with a clean, sharp knife or a pair of pruners. A leaf node is a swelling on the stem where a leaf or stem emerges. The cutting should have at least two pairs of leaves, so will need to be about 3 to 5 inches long.
Pull off the leaves from the lower half of the yellow crabapple stem, and cut the upper leaves in half across, removing the tip. Reducing the size of the upper leaves will require less moisture, energy and space.
Fill a 4-inch container with a mixture of half perlite and half sand. Put it in a shallow dish of water and let the potting mixture wick up the moisture until the soil is damp clear through.
Plant the cutting in the damp potting mixture and put the container in a warm, sunny spot. However, don't put the container in a windowsill, which will be too hot as the plastic will magnify the light.
Make sure the atmosphere in the container stays constantly damp, and if the soil appears dry, remove the container and set it in a dish of water until it's damp. Don't allow the soil to become soggy, which can cause the stem to rot.
Look at the bottom of the container after about a month. If you see tiny, white roots, the cutting has successfully taken root. Remove the plastic, but continue to keep the soil damp. Plant the new yellow crabtree outdoors in the spring, when the weather warms up and any danger of frost has passed.