Germination of Japanese Honeysuckle, Lonicera Japonica Seeds

Lonicera japonica, or Japanese honeysuckle, is a perennial flowering vine. Although it’s lovely, with tubular, white, heavenly-scented flowers, it is considered invasive and a weed in some states. Spreading by underground rhizomes and surface runners, Lonicera japonica climbs on other plants or creeps along the ground. The seeds are small and germination is slow. Start the seeds indoors in the winter and plant out in the garden in spring.

Moisten a handful of sphagnum peat moss and wring it out to remove the excess moisture. If it is still wet, set it aside until it is just barely moist. Push the Lonicera jamponica seeds into the peat and place the bundle in a plastic sandwich bag. Seal the bag and place it in the refrigerator. Leave it in the refrigerator for 60 days.

When you are ready to plant the honeysuckle seeds, fill  a standard nursery flat with equal parts of potting soil and sphagnum peat. Water the mixture until it is saturated and allow it to drain completely before planting.

Place the seeds on the surface of the soil and then cover them with a 1/8-inch layer of peat. Distance apart is unimportant at this point because you will be transplanting them before they become too large and begin to crowd one another.

Squirt the surface peat layer with water from a misting bottle, cover the flat with plastic wrap and place it in an area with bright, indirect sunlight. The plastic wrap should hold moisture in the soil but check it periodically. If the seeds dry out they will not germinate. They should begin sprouting within 30 days.

The seedlings require consistently moist soil and lots of sunlight. To learn more about L. japonica seed germination, visit the U.S. Forest Service website.


Note: Contact your county cooperative extension office to find out if L. japonica is considered invasive in your area.

Photo: Courtesy of:  William Rafti of the William Rafti Institute