Forty percent of the catnip seeds planted in 2005 germinated, though this number would have been higher if the seeds had not been raked after dispersal. The rate of germination might also have been higher if a cover crop had been planted for water retention. Of these plants, very few were large enough to harvest. Of the plants the germinated in 2004, only half survived.
The primary objective was to plant a test crop of Nepeta cataria (catnip) using seed to determine if it can be grown for commercial production in the Montrose area of Colorado. Specifically, we were looking for a crop that can grow on the Western Slope and be economically stable.
We also plan to determine how this plant behaves in our climate over the winter and to see if it acts an annual or a perennial.
In the spring of 2002, catnip seeds were planted with fertilizer using a truck seed spreader. We irrigated and waited two weeks, but nothing grew but weeds. We found some documentation that indicated catnip seeds need to winter-over before they can germinate. According to this source, the seeds have a hard exterior shell that needs the cold to crack them open for germination.
In late fall we had a new batch of seeds disbursed over the area, and we put up fencing to protect the plants from grazing animals in the spring.
In April of 2003, we began irrigating, but only weeds grew. We hypothesized that we might have covered the seeds too deeply when we marked the rows. We decided to wait until early fall to plant again. To help with irrigating we installed an aerial sprinkler irrigation system for the field. We also added manure-free compost to the area to increase the amount of organic material in the soil.
In October, we tilled the upper half of the field and spread the seeds (1:10 ratio of seeds to fertilizer) using a hand spreader. By June 2004, 10% of the seeds had germinated. From June on, we irrigated the field as needed every three to five days, running the sprinkler for 30 minutes.
By August, about 40% of the seeds germinated, ranging in size from ½” high to 24” high with blossoms. This same month I began starter trays of Nepeta cataria from seed. In half the trays, I sprinkled seeds on the surface without any soil covering them. The other half I covered lightly with soil. The trays where the seeds weren’t covered germinated quicker and in a larger quantity than the other seeds.
We concluded that the best method for seed dispersion was by hand with a fertilizer spreader, though the standard truck spreader application should also work.
If Nepeta cataria can be successfully grown on the Western Slope, a new stable market will open for farmers, as the market for insect repellant is large and increasing with population growth.
Producers I’ve spoken with are very anxious to see what the outcomes of my project are. Several have expressed an interest in converting their hay production land to catnip if this proves to be financially profitable.
In this field, I have soil high in salts and low in organic material. The addition of non-manure compost helped with the seed germination. It seems the germination rate would have been even higher had I not raked the seeds after they were dispersed onto the soil. I also believe the rate would have been higher if we planted a cover crop to aid in soil moisture retention.