Yard and Garden: Sprouting avocados, rooting pineapples

AMES — Wondering how to sprout an avocado seed or root the top of a pineapple? Iowa State University Extension and Outreach horticulturists share information on propagation. To have additional questions answered, contact Hortline at 515-294-3108 or at hortline@iastate.edu.

How do I sprout an
avocado seed?

To sprout the seed, remove the large seed from the center of the fruit and wash it in water. For propagation purposes, the broad end of the seed is considered to be the bottom. The pointed end is the top. Insert three or four toothpicks into the sides of the seed. They should be placed about halfway up the pit. Then suspend the seed in a glass of water. The bottom one-fourth of the seed should rest in water.

The seed should sprout within a few weeks. During this time, periodically add water to maintain the initial water level. If it doesn’t sprout within two to three months, discard the original avocado and begin another. The roots are usually the first to emerge from the seed. The stem appears later. Pot up the seedling when the roots are 2 to 3 inches long.

Remove the toothpicks and plant into a 6- to 8-inch-diameter pot using a commercial potting mix. Position the seed in the center of the pot. The top of the seed should be level with the soil surface. After potting, water thoroughly; then place the plant in a brightly lit location. A location near an east or west window is ideal. Water the plant regularly. Keep the potting soil moist, but not wet. Fertilize once or twice a month in spring and summer with a dilute fertilizer solution.

How do I root the top of a pineapple?

Select a large, fresh pineapple at your local grocery store. At home, cut off the top of the pineapple about 1 inch below the cluster of leaves. Trim away the outer portion of the pineapple top leaving the tough, stringy core attached to the leaves. Also, remove a few of the lowest leaves. The pineapple top should then be allowed to dry for several days. The drying period allows the moist core tissue to dry and discourages rotting. After drying, insert the pineapple top up to the base of its leaves in perlite, vermiculite or coarse sand. Water the rooting medium. Keep the rooting medium moist, but not wet, during the rooting period. Finally, place the pineapple top in bright, indirect light. Rooting should occur in six to eight weeks.

When the pineapple has developed a good root system, carefully remove it from the rooting medium. Plant the rooted pineapple in a light, well-drained potting mix. Water well. Then place the plant in bright, indirect light for two to three weeks.

After two to three weeks, the plant can be placed in a sunny window. Keep the potting soil moist, but not wet, with regular watering. Using a dilute fertilizer solution, fertilize pineapples once or twice a month in spring and summer, but only once a month in fall and winter. Plants can go outside in late May, but must come back indoors before the first fall frost.