Something Eating Potato Leaves!

Has anyone had the shock of finding all the leaves eaten off a potato stem/vine? My plants are in large pots and the stems have gotten quite long as I neglected to add more soil as they grew, but a couple days ago I went out to find every leaf chewed off the stems. The stems are now wilted but still green and I have no idea if my potatoes will reach a good size or not. It's too early to pick them. Does anyone know what eats the leaves as I thought they are poisonous - like tomato leaves and other nightshade leaves (also like rhubarb)??  I am also losing my tomatoes and their leaves are being chewed off/eaten up by something. I sure would like to know what is going on!

I rarely get potatoes that live their full lifespan.

Lady bug imposters chew mine to bits every season. They like all the nightshade family plants, especially tomatoes and potatoes. Planting them near each other is dangerous for for me, but I don't make that mistake anymore.

Could be something else, but that's what ate mine.

Denise said, " Does anyone know what eats the leaves as I thought they are poisonous - like tomato leaves and other nightshade leaves (also like rhubarb)??  I am also losing my tomatoes and their leaves are being chewed off/eaten up by something.

If you are having a drought like we are having where you live just about any and every critter might be suspected of eating those leaves.

Tomato leaves are not poisonous as everyone thinks.  There are posts and a book on the forum about eating tomato leaves.

I only grew potatoes once though I had voles eating mine.

I have no idea if your plants can be saved though covering them with something might help.

I also cannot grow English potatoes, some kind of small beetle just demolishes the leaves. I've tried growing a few special varieties and they have to be grown under total cover (not a big deal, since they don't need pollination).
As for tomatoes, everything eats them too, I have to grow mine in winter in a greenhouse to avoid that. Grasshoppers seem to be the most usual suspects for large-scale destruction, although the hornworms can do some serious damage too (growing in winter avoids the worms, but hoppers are more common here in winter).

Hi Denise,
In our area the Colorado potato beetle is the most common pest for potatoes. (Picture below, compliments of Wikipedia). However, they are not an overnight sort of pest. They will eventually strip plants bare, but it takes time and generally has babies and you see them getting bigger. Grasshopper could do it, but if there was enough to strip it as suddenly as you describe then I would expect other damage to trees, plants, etc in the area. Hornworms (while I have never seen them on potatoes), again could eventually strip them, but it's not a sudden thing for all the leaves to be gone. I would suspect something bigger such as a rabbit or ground hog. Have you seen any evidence of anything of that size around?

**Edit**
PS - You can pick potatoes at any point in their growth to eat. The baby potatoes the size of a quarter or half dollar are particularly good. You don't get as much bang for the buck from the plant, but if they don't regrow leaves, you might as well eat what is there.

I've seen those little black flea beetles on potatoes once in a while, but they don't seem to hurt too much. These critters Colorado Potato Beetle, on the other hand can do a lot of damage.  

Are you in a region with tomato/tobacco hornworms?  In the USA, that's nearly everywhere except the Pacific Northwest.

So I came from the PNW to the desert SW and had no idea how much a tomato hornworm could eat or how fast.

They are impressive in many ways.  They can hide in the leaves for maybe a few weeks, slowly gaining in size and then *BAM* suddenly a whole plant is stripped overnight.  At that point the caterpillars are quite large.  Even as big as they are they can be hard to see as they camouflage well. Then the caterpillar drops into the ground, burrows in, pupates and becomes a hawkmoth.

In the southern Arizona desert these hawkmoths are pollinators of the stunning native Night Blooming Cereus cactus. That cactus is now becoming rare. It's flowers aren't getting pollinated as much as needed to keep increasing the population. This is believed to be due to the use of pesticides in farming dramatically reducing the hawkmoth population.  Here is a quote from the Arizona-Sonora Desert Museum

Desert night-blooming cereus plants usually occur as widely-separated individuals, and the flowers are not self-fertile. The flowers are cross-pollinated by hawk moths (Sphingidae) which fly hundreds of yards between plants in their search for the nectar reward. The cactus fruit turns red when ripe, attracting birds that eat the pulp and disperse the seeds in their droppings. The root is used medicinally to treat diabetes and other maladies.

This cactus is a desert version of the canary in the coal mine, an early warning that something is wrong in the ecosystem. Where pesticides are heavily used in agricultural areas adjacent to natural habitat, the hawkmoth populations are devastated and most of the flowers fail to fruit. This is an example of chemical habitat fragmentation; the habitat appears to be intact, but some of its ecological processes have been destroyed or degraded.  

So when I catch them here, I put the caterpillars on other nightshades in the yard, ornamentals so they can continue their lifecycle.  I've been doing this for three seasons now and I have no increase in hornworms on my plants.  Instead, the amount of the caterpillars I've had on tomatoes has gone down each year. I attribute that mainly to growing larger and larger permaculture gardens which are creating more predator bug habitat. Permaculture is awesome. I love letting nature do the work.

Here's an article about hornworms, and talks about using sweet alyssum and buckwheat to attract Trichogramma wasps which parasitize these caterpillars.
Tomato Bible website - the Tomato Hornwom

I find it's easiest to pick them off. You can find them easiest at night with a UV light. Their white stripes illuminate brightly.  I was a little late in the photo below and they were huge.  That was our first year here and being from Oregon, I forgot that tomato hornworms existed until some of the plants were stripped. Now I watch for them and still pick them off, and it's way less of a task than in the first year gardening here.  Thank you wasps, lacewings, and ladybugs!

They are also used for lizard food, but I think people feed them other plants for that purpose  If you look on Amazon, you can find lots of enterprising sellers providing hornworms to lizard enthusiasts.

Kim Goodwin, Those are lovely fat hornworms! I've seen a few that size in the past I do not see any this year. There was also a year when giant moths would visit the evening primrose when they bloomed at night. I never knew they were hornworm moths, also thank you to Mark, Matt and others explaining about the various bugs!  Am seeing few bugs at all, but many sow bugs under things where it's cool. I  have never seen a Colorado Potato beetle in these parts.  I have tons of squirrels and maybe a couple tiny grey grasshoppers but I suspect the lizards are keeping that population down. There have been lots of lizards for several years now and almost no bugs or spiders. I used to see skunk, racoon and rabbit, but rarely if ever now. Even the deer are fewer and looking thin. I suspect whatever is eating the potato leaves is really hungry. The tomato and other veggies (cucumber, pepper, eggplant, even zucchini all purchased as organic heirloom starts) are all struggling to grow and the potato vines are scrawny, so it's not a huge loss losing the leaves as there is hardly a spud to show for the effort.  There are few to no flowers on food bearing trees, vines and bushes (blueberries, raspberries, etc) and the perennials are not growing like they used to. What fruit sets on is dropping off or drying up before ripening.   I have an old huge sturdy lavender bush but this year the flowers are half the size and there are only a few (less than 20 at any time) bees enjoying the flowers where as before they covered it as a buzzing cloud. It makes me sad to see this happening, altho I have been expecting it.  Still we may feel blessed by our Creator with life and our daily labor of caring for one other and for our ailing world.  Insights abound in the Creator's Good Book - see for example Habakkuk 3:17.

I would take those horn worm fishing and see what happens