Species That Won't Cross-Pollinate With Jalapenos

Pollen in Motion

• Cross-pollination occurs when pollen from one variety pollinates the flower of another variety, resulting in offspring that are a mixture of genetic traits from the two varieties. If you save seeds from a jalapeño plant that experienced cross-pollination, the seeds will grow into plants with unpredictable characteristics. Peppers are classified as a self-pollinating crop, meaning that a pepper flower can be pollinated by its own pollen. But unlike other self-pollinating crops such as peas (Pisum sativum), peppers are highly susceptible to cross-pollination caused by insects.

Many Peppers, One Species

• All common garden peppers have the scientific name Capsicum annuum. This means that sweet peppers and hot peppers -- despite their vastly dissimilar culinary qualities -- are only different varieties of the same vegetable, and thus Jalapeño peppers are in the same species as all other peppers you are likely to grow in your garden. The scientific definition of a species is a group of organisms that are capable of reproducing with each other, so any common pepper cultivar can cross-pollinate with any other common pepper cultivar.

One Exception

• One type of pepper can be safely grown around your jalapeño plants: the tabasco pepper, essential ingredient in the widely known hot sauce of the same name. Tabascos (Capsicum frutescens) are the only familiar peppers not in the annuum species, and therefore they are the only peppers that will not cross-pollinate with jalapeños. You can grow tabasco peppers if you live in a warm climate with a long growing season -- both the Southeast and the Southwest are suitable regions. Decent production is possible in the central states if you grow the plants in a greenhouse for two to three months before setting them out in the garden.

Peppers in Isolation

• Considering the delightful diversity of shapes, colors and flavors offered by the numerous pepper cultivars, most gardeners would not want to limit themselves to growing nothing but jalapeños and tabascos. You can minimize or eliminate cross-pollination by physically isolating the flowers of your jalapeño plants from the pollen of different varieties. In a home garden situation, 65 feet will often provide adequate isolation, and 500 feet will almost guarantee seed purity.