How to Get Rid of Spinach Leafminers
Spinach leafminers burrow into the leaves of growing greens and eat them from within, making your favorite spring greens unpleasantly inedible. But with a little know-how and quick action, you can keep these pests out of your garden. Here’s how to prevent and get rid of spinach leafminers so you don’t miss out on a single green smoothie, salad, or sauté.
What are spinach leafminers?
Spinach leafminers are the larvae of tiny flies (Pegomya hyoscyami). Adult flies overwinter as pupae and hatch in the spring. Females puncture leaves and then lay eggs within them. The eggs then hatch and the larvae begin feeding on the leaves. Although they’re called spinach leafminers, these pests also damage similar plants such as beets and chard.
How do spinach leafminers damage plants?
Larvae burrowed in the inner layers of the leaves eat them from the inside. Most leafminers create unmistakable meandering mines or trails inside the leaves, but spinach leafminers merge their mines to make large blotches. The “mined” areas dry out and make leaves unattractive.
How do I prevent spinach leafminers?
Spinach leafminers are most common in gardens in which plants in the Amaranth family (which includes spinach, beets, and chard) are grown continuously and overwintered. There are three primary ways to prevent spinach leafminers:
- Rotate crops regularly.
- Attract parasitic wasps, a natural enemy. Herbs like cilantro, dill, and fennel will lure them in.
- Weeds can also play host to spinach leafminers. Be sure to keep your garden thoroughly weeded.
- Row covers may also be beneficial if put in place before the insects become active in the spring.
What should I do if I have spinach leafminers?
Most mines occur on the first leaves of the season. Keep a watchful eye, checking the undersides of early leaves. If you see mines or peel open the affected area and see a tunnel that is either hollow or contains white larvae, clip off the affected leaves. If addressed early, spinach leafminers usually won’t cause a problem on the majority of your crop.
Need more info and local pesticide recommendations? Contact your regional Extension agent. You can find the nearest Extension office through the Cooperative Extension System map.
Spinach leafminers can make for a stressful start to your spring garden, but they don’t have to ruin the season. By staying vigilant and acting quickly, you can limit leafminers to the first few leaves of the year and enjoy plenty of delicious spinach, beets, and chard in the months to come.