Growing catnip from seed

Asked January 27, 2015, 1:52 PM EST

What are the conditions required of a grower to successfully germinate and grow catnip in a greenhouse environment for transplant to field? Is scarification or stratification of seeds, or both necessary for germination? Are there other unknown conditions we should be aware of that will increases the success of the growing operation?
Thank you.

Huron County Michigan

1 Response

When planting catnip seeds, the best results can be achieved through the use of proper seed preparation, adequate spacing between seed rows, and appropriate watering. As the first step, a process of freezing and refreezing catnip seeds will allow them to germinate more easily. Transplanting seedlings several inches apart in a garden bed, then thinning seedlings as necessary after they have produced two sets of leaves will help produce prime growing results. Keeping catnip seeds moist with a mister, rather than overwatering, is one key to success with these plants indoors or outdoors.

To fully prepare catnip seeds for germination, it helps to break down the tough seed coating. One way to achieve this goal is by putting seeds in a plastic baggie in the freezer for one month. Next, let the seeds thaw completely, and then freeze them for one additional month. Finally, let the seeds thaw again overnight by immersing them in warm water.

Nepeta cataria, sometimes known as catmint, can grow up to 4 feet (120 cm) high. The spacing of plants is important for successful growth. Ideally, plant catnip seeds with about 15 inches (38 cm) between rows. Transplant the seedlings outdoors to a sunny bed after the last spring frost, allowing a spacing of about 20 inches (50.8 cm) between plants.

Catmint is a common name for plants from the genus "nepeta," a group within the "Lamiaceae," or mint, family. Another common name is catnip. Both names come from the euphoric effect some members of the genus have on cats. This effect is created both by dried and living forms of those plants.

The effect on cats may be compared to inebriation in humans. It is believed to be brought on by the way chemicals from the plant mimic cat pheromones. The effect is inherited genetically, and though all varieties of felines — including lions — may experience it, specific cats may be immune to the effect.

Members of the nepeta genus are herbaceous, meaning their stems are non-woody and die off after the growing season. Catmint is also perennial, meaning that only the parts of the plants above ground die off, and the plants grow back the following season from the underground portions. Catmint is a flowering plant, and the normal blooming season begins in early summer; the plant is capable of blooming repeatedly throughout the season.