Nothing tastes better than fresh-picked fruits and vegetables.

Unfortunately, invasive pests threaten to devour the crops in our gardens and farms, and the flowers, trees and plants in our landscapes. They are a real threat, costing our nation roughly $120 billion each year.

These pests can spread quickly as they come from other countries and have few or no natural enemies here.

In particular, the U.S. Department of Agriculture, or USDA, cautions gardeners to be wary of 19 destructive, invasive species known as Hungry Pests, which include the emerald ash borer and Asian citrus psyllid.

People need to be aware of these pests, because they are primarily spread in the things people move and pack.

Fortunately, homeowners can follow these easy tips to protect their gardens and landscapes, and help keep Hungry Pests from spreading:

• Only buy plants and seeds from reputable sources, such as established nurseries or online businesses. Ask where they buy their plants and if they comply with federal quarantine restrictions.

Temporary, roadside vendors — and even non-established dealers online — may not be doing what is required to keep plants free of pests.

• If you are in a quarantined area, don’t move plants or homegrown produce. And to be safe, don’t bring back plants from other areas, including abroad.

That’s how the Mexican fruit fly — which threatens 50 types of fruits and vegetables — entered the United States.

• When doing property cleanup, call your local USDA office to find out how to safely dispose of trees, branches and other yard debris. Moving such materials outside your property in quarantined areas could spread invasive pests. Make sure your contractors also follow the procedures.

• Don’t move homegrown citrus or citrus plants outside your property. That’s how citrus greening, a disease that is killing America’s orange groves, has spread.