Catnip is a common herb that thrives in much of North America and is very easy to grow. While you’ve probably heard that catnip makes cats something like tipsy, you might not know that this effect is an inherited trait and does not affect all cats.
Catnip can be planted in your garden in spring or fall, from seed or plants. It will sprout in two to three weeks if started from seed. Catnip grows to a height of three or four feet and has featherlike, light green foliage and small clusters of lavender flowers that grow on spikes. A member of the mint family, catnip is also used in food and herbal remedies. For example, tea made from the leaves and flowers of Nepeta cataria is said to relieve coughs. The oil extracted from catnip plants is even used in natural mosquito repellents.
Planting Catnip
Catnip can be planted in your garden either from seed or from plants.
If you’re growing catnip from seed, you’ll need to properly prepare the seeds. Catnip seeds are tough and need to be stratified or slightly damaged before they will sprout. This can be done by first placing the seeds in the freezer overnight and then placing the seeds in a bowl of water for 24 hours. This process will damage the seed coat and will make it much easier for the catnip seeds to sprout. After you have stratified the seeds, you can plant them indoors or outdoors. Thin them to one plant per 20 inches after the sprout.
You can also plant catnip from plant divisions or started plants. The best time for planting catnip starts or divisions is in either the spring or fall. Catnip plants should be planted 18 to 20 inches apart.
How to Grow Catnip Plants
Catnip grows best in the full sun combined with average, well-drained soil and regular watering. Cutting the plants completely down after the first bloom set will allow enough time for it to completely regrow and bloom again.
To avoid damage from unwelcome neighborhood cats, consider protecting your catnip with some type of enclosure. Insects and rodents are not a problem, and catnip does not tend to suffer diseases.
Lighting
Catnip plants need full sun locations, preferring at least 6 hours of sun exposure every day but liking shade in the afternoon when grown outside in hot climates. When growing containers indoors set them on a sunny windowsill of a south or west-facing window.
Rotate containers every couple of days to prevent plants from bending towards the light, a phenomenon known as phototropism.
Plants will become leggy if they do not get enough sunlight. Simple growing lights can be purchased online or at a local nursery to supplement indoor lighting conditions if necessary.
Water
Plants are drought resistant and prefer the soil dry to out slightly between waterings. Allow the top inch of potting soil to dry out before giving your plant water. Then saturate the container until water freely drains out the bottom.
Fertilizing
Like mint, and other herbs bearing essential oils, it is recommended to not fertilize your catnip. Fertilization encourages prolific vegetative growth and reduces the quality of the oils in the foliage and flowers.
Pruning
If your plants aren’t occasionally trimmed back they will become scraggly. Regular pruning encourages bushier plants.
After your catnip flowers, cut the plants back to 3 to 4 inches above the ground. Within a couple of weeks, it will grow back; this new growth will trigger a new flowering cycle.
To prevent insect or disease problems remove dead or dried leaves regularly.
Varieties of Catnip Plants
- Nepeta cataria: Preferred by cats; deer-resistant but attracts butterflies
- Nepeta mussinii: Attractive ornamental plant that grows to about one foot tall; often used as a ground cover and also attracts butterflies
- Nepeta x faassenii: Produces oval, intricately veined, gray-green leaves and abundant lavender flowers, from spring through autumn; not as invasive as other Nepeta species