Leaf Miners in My Spinach

Back on the first gorgeous weekend of April, I eagerly planted several rows of spinach, lettuce, chard and beets. Within days, little green things began to emerge from the Earth in nice straight rows. I was very, very excited. Ah, farming!

It’s been a hectic six or seven weeks. I was gone 10 days in April, and so far I’ve been home just five of the 18 days in May. Even so, I’ve made a point to poke my head into the garden to see what’s going on and keep the weeds in check.

Well, the day before I headed off on my most recent 10-day trip, I noticed a few white spots on my spinach leaves, which at that time were about 4-5 inches tall. I wasn’t sure what they were, and honestly, I didn’t have time to find out. I chalked it up to spotting caused by my fertilizer solution.

Spores? Fungus? Bacterial infection?

Back from the trip, I headed right over to the garden. The spots had enlarged and more plants were affected. Different leaves were in various stages of what, I didn’t know. The smaller spots were white, and some of the leaves appeared translucent. Some of the leaves even had pinpoint-sized black spots that looked like spores.

Oh, no! I couldn’t bear the thought. And I was headed out of town again in just two days. The prospects of a big spinach salad were looking slim.

I come back home, head to the garden, and this time whatever the culprit is had jumped over two rows of lettuce and onto my chard and beets. Goodness gracious. Time to start pulling, I thought. Other than a few Google searches for bacterial infections on spinach, I hadn’t really made an effort to find out what caused it. So, I snapped a photo and posted it to my Facebook page.

The thing about my line of work is that I have some friends who do pest ID professionally as County Extension agents and pest consultants. Those folks can come in handy, I tell you. I posted the photo on Sunday early evening, and by Monday morning, I had a diagnosis: leaf miner.

What are leaf miners?

A little larva was eating its way through the middle of the leaf, they said.

I ran straight over to the garden, and wouldn’t you know, I found those sneaky guys. A small winged insect had laid eggs on the leaf (those initial white spots), and the subsequent larvae were eating the translaminar portion of the leaf to its heart’s content. It’s amazing to think something is small enough to fit between the top and bottom layers of a leaf, but there they were.

Stopping leaf miners

So was my whole crop in trouble? Would it move to my lettuce? Infest other veggies I plan on planting later on? Apparently this leaf miner is specific to plants in the Chenopodiaceae family—that is, spinach, beets, chard, and some weeds. My bug friends said to remove the affected leaves and those nasty weeds, and the emerging leaves should be fine.

It took less than an hour’s worth of work. I’ll keep an eagle eye on them, of course, and remove any white-spotted leaves I see.

I can have a nice spinach salad, after all.