Every spring when I was in elementary school my mother would take me to the neighborhood garden center to buy a starter-pot of catnip, nepeta cataria. We would plant it in the herb garden in the afternoon and by morning it was gone. Well, not totally gone. Our three cats that were born with white beards, and cheeks had beards and cheeks stained green. They even smelled antiseptic like a cross between lemon and mint.
My mother would have saved money if she had read Philip Miller's The Gardener's Dictionary. In 1754 he wrote, “If you set it, the cats will eat it. If you sow it, the cats don't know it.”
Cats are attracted to the chemical nepetalactone in catnip. Cats can smell nepetalactone one part in a billion in the air. When the leaves are bruised in transplanting the herb the fragrance which cats equate with a sexual attractant is released. Not all cats roll in catnip and go into a hallucinogenic trance. To respond to catnip the cat must be at least six months old or sexually mature and have inherited the right genes. The response is an inherited “autosomal dominant trait.” It is estimated that 15 to 25 percent of all cats lack the trait and are immune to the scent. Even cats that re-act to catnip usually get “high” for less than 15 minutes. They will leave the catnip alone for a couple of hours and come back for a re-charge.
Why Grow Catnip?
Growing your own catnip is the only way to ensure your cats get good quality. When catnip toys are purchased you have no way of knowing how much catnip is used with the stuffing or if it is fresh. The pet-toy-product industry often responds more to price than quality. Toy-grade catnip even if it is certified organic is what is leftover after the best leaves go to the medicinal and tea market.
Stems and leaves that have been poorly dried (grey not green) have little aroma.but are often ground-up and sold to cat guardians.
Growing catnip from seed where it is intended to grow is easy only if you let it do what it does best – come up on its own terms. My mother may have failed with the plants but I failed by following the directions on the seed packs. The instructions say to lightly cover the seeds with dirt. But, think about how catnip comes up in the wild. It drops its seeds on the ground in Fall and they germinate when the temperature is right (around 65-70 F.degrees) in late spring or early summer. In nature no one lightly covered the seeds.
Catnip Bed
Catnip grows best in well-drained sandy loam. If clay soil is your yard amend the soil with lots of compost. As with most herbs it needs at least six hours of direct sunlight everyday. It is important to select a garden area that has been weed-free for several years. Catnip is a perennial. If the planting area is infested with weed seeds or roots the weeds will grow through the catnip destroying the plant crown.
Avoid augmenting the soil with synthetic fertilizers because they give plants a quick jolt of nutrients resulting in fast lush growth and herbs with reduced essential oils. Work in some composted steer manure just before the seeds are sown. When the plants are a foot tall side-dress with grass clippings on an annual basis. The grass clippings will supply nitrogen to the soil.
Just before sowing the seeds – and the seeds can be sown anytime, they know when to germinate – make a soil ridge or rim around the row to keep the seeds from washing away when it rains or they are watered. Keep the soil moist until the plants are well established, than deep-watering once a week should be sufficient in summer. The plants grow best when the plants are spaced 15 to 18 inches apart.
When temperatures drop to 20 degrees in winter the catnip will die-back but it is one of the first plants to re-appear in the garden when the temperature gets just above freezing. The crown of deep-green toothed elongated heart-shaped leaves that appear are frost tolerant. When the plant gets about six to eight inches tall start picking the leaf whirls above the first node to make the plants bush out. This can be done on a daily basis to give kitty a fresh daily treat.
As the season progresses the catnip will grow into a 2 to 3 foot tall bush with grey-green slightly downy leaves and spikes of tiny white flowers tipped with purple or pink. Just before the flowers open cut the catnip down to within 6 inches of the ground.to dry it. Waiting longer and all the plant's energy will go into producing the seeds and the leaves will have less essential oil.(Letting one plant go-to-seed is a great way to get more plants to keep the catnip bed young and vigorous.)
Drying Catnip
To successfully dry catnip find a clean, dry, dark place with cross ventilation or use a fan to move the air around. Avoid any room with high humidity like laundry rooms, bathrooms and kitchens. Pick the catnip in mid-morning after the dew has dried from the leaves. Picking it immediately after a rain or with dew on it makes it difficult to dry the herb without mildewing. Picking catnip in the heat of the day results in leaves that are losing essential oils to the warm air.
Tie several branches together to dry remembering that the less stems drying together the more air the branches receive and the faster the herbs will dry. Hang the bouquets upside down to dry. Every couple of days re-bundle the herbs moving the inside branches to the outside to keep mold from developing. The complete drying process should take about 7 to 9 days. If it takes longer the quality will suffer. This will be visibly noticeable with the leaves becoming grey or brown.
When the herb is “crisp” (dry) remove the leaves and store them whole. Crumbling the leaves should be avoided until the catnip is used because crumbling or pulverizing the herb releases the essential oil.
Nepetalactone in catnip is UV photosensitive – it is destroyed by light. Store the dry leaves in an airtight opaque container.. The best storage temperature is an even temperature somewhere between 50 and 70 degrees. Cookie and fruit-cake tins make good storage receptacles. Lacking those spray paint (make opaque) the outside walls of large glass jars with tight lids. Catnip should never be stored in plastic bags because cats can tear them open and suffocate in the process. And, all plastic including rigid containers are poor storage choices because plastic is permeable both absorbing the essential oil from the herb and giving off whatever previous essential oil the container had absorbed.
Catnip and Us
While catnip on us humans does not make us go into ecstasy the dry leaves are found in many “soothing” herbal tea blends and the fresh green leaves can be added to salads. Before tea was imported from the Orient, catnip tea was the most drunk tea in Europe.
And, rubbing some catnip leaves on ourselves might not be a bad idea the next time we go on picnic or camping. The essential oil of catnip has been found to be ten times more effective than the chemical DEET to repeal mosquitoes.
Catnip is as lovely as any ornamental in the garden. Being an herb its essential oils are good at keeping pests and disease away. Its flowers also attract bees and butterflies.
