How do I keep squirrels and rats from eating my grapes?

My beautiful picture

I’m running an experiment this summer on our grape arbor. Using our CritterCam, I’ve photographed both squirrels and rats munching on grapes. I decided to see if either paper bags or plastic clamshell containers would deter the daily and nightly mammalian fruit buffet. Preliminary results:

  • Clamshells don’t work. The fruit fermented, and not in a nice way.
  • Paper bags seem to work, but probably only because I left a lot of the fruit exposed in the hopes that they would eat that first and leave the bagged fruit alone. It’s also hard to tell when the fruit is ripe when it’s in a paper bag.

I’m thinking the long term answer is to make custom fruit cages out of hardware cloth. If the grapes were neatly tended on a vine it would be much easier to net them. Netting is not an option on our arbor.

Look carefully in this image and you can see one of the “perps” reaching out to grab a tasty grape:

My beautiful picture

Have you tackled the mammalian grape buffet issue? How did you deal with it?

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15 Comments

  1. similar goings on up here in Cupertino. Instead of wood crossbeams, we have steel cables across our patio. I’m thinking of snipping some big pieces of metal out of aluminum catering trays to make some barriers between the roof and the cables, but that might be too much work for little return – there are about 10 cables.
    I also wondered about doing something with hot chili peppers, but figured much of it would blow away in the wind. Maybe a hot chili spray for the whole vine? I know dog owners have a spray called “bitter apple” to deter their pets from chewing on stuff. If either of those would wash off easily I’d use it.

    Assuming that your trellis is connected to your house roof, what about some sort of sticky barrier between the two? We used to smear around a sticky gel called Tanglefoot to keep squirrels from chewing on some of the beams of our house when we lived down in Silverlake. It was pretty weatherproof and lasted for a good 6 months. Animals didn’t like to step on it.

  2. I made wire mesh cages (1/2″ hole) for my bunches of bananas and also finer mesh for individual sweet corn cobs.
    They work really well and stop rats, bats, birds, possums etc.
    I’m sure I have heard squeals of apparent frustration at night as they go crazy for ripe bananas.
    I found tree rats will chew through anything else – for instance 3 layers of plastic bags.

  3. If you figure it out, let us know. The roof rats ate all my eggplants, ruined cucumbers and zucchini, and burrowed in the tomato bed which ensured I dug them all out the following weekend.

  4. Did you consider putting vent holes into your clamshell containers to allow air?

    I save quart-size wonton soup containers (hey, every once in a while we get a hankering for wonton) for transplanting veggies, because they’re nice and deep. To allow for drainage, I use a metal kebab skewer whose tip I heat up on my kitchen stove and which, when hot, makes a nice neat hole. Maybe putting a bunch of holes in your clamshells would help prevent fermentation.

    Another suggestion is plastic net produce bags from onions and the like. I use them to protect strawberry plants in the garden from marauding chipmunks and they seem to work well. I would have thought that the chipmunks could just chew through them, but they don’t seem to want to bother.

  5. I have covered up with a plastic covering. It enhanced protection from it put some lemon or lime to sour away the squirrels and rats. Hope this helps, let me know what the turnout.

    • I love the principle… But with just a little bit of land, sometimes there’s nothing left after the “gleaning”!

  6. We ran an electric fence/wire around the bottom of our grape arbor, about 12″ up and 6″ out. Plug it in at night… 100% keeps the raccoons from the grapes. I don’t have rats, so you would probably need a 2nd wire closer in. Bought the electric fence charger on craigslist for $10.

  7. Our cat keeps most birds and other marauders out of the peaches and berries… (No grapes yet–they’re a couple years down the road.) Obviously not an option for everyone, though.

  8. We got fake fruit from the dollar store and wired it to our trees, vines, etc, the critters try to eat it when they’re not fruiting, figure they don’t like it, then when the real stuff comes on, they don’t bother it as much.
    You could try something similar, covering what you have and wiring up fake grapes for them to munch on.

  9. I really really LOVE the idea of fake fruit frustrating the local wildlife! I have a veggie garden in Suffolk, England – dry and sandy – and the main problem is ruddy MOLES. If I don’t water, the seedling die, if I do water, the moles say Whoopee! Damp ground and lots of bugs! and leave great tunnels under the seedlings, so they die.
    I staple squares of plastic around my apricots, easy as I only have nine.
    The grapes, I net the whole vine, and go and let the wretched blackbird out most mornings.
    this year, the pear tree has an exceptional crop, too many to “staple”, too difficult to net, so I am just crossing my fingers and hoping.
    I am getting more and more sneaking sympathy for the car sticker: Preserve Wildlife: Pickle a Squirrel!

  10. I’ve seen sprinklers connected to motion detectors that work for deer and raccoons, maybe you could get them to work for smaller varmints also.

    After losing all our strawberries again this year despite having a cage over them, I’m trying to solve a similar problem as you guys!

  11. This is the second year that we’ve lost (not an end yet, but I see it happening) our battle to save our grapes. Our grape vines climbed on top of our patio cover.

    We’ve tried spraying concoctions made out of garlic, onion, and chili peppers. The last time we had hope was when we kept on spraying every other day and all that work went to drain with the big storm that we just had in SoCal. The rain washed off the spray nicely.

    We’ve also bagged the grapes (the ones that we can reach). And the bags were ripped open.

    I know for a fact that we have birds and squirrels. We’ve also seen raccoon in our backyard last year. So I attribute most of loss to raccoon.

    I have already started thinking about what to do next year and I’m at a loss. Maybe we’ll try Jeff’s idea of wire mesh cage? Jeff, do you have a picture of the cages that you used.

    I really hope that I won’t have to use electric fence/wire as it seemed to work for Valri. But, do I have much choice left?

    Will look forward to learning more tricks here. It will be the third year for the grape to bear fruits and I can only imagine the crop to be bigger. So far, I’ve only been lucky enough to have 2 red but sour (premature) grapes. See, this guy doesn’t mind the sourness. There’s no way we can compete with him. Sigh…

  12. My Chardonnay grapes are espalier on six “airplane cables” across the patio, well below the roof line. This is the first year the rats have hit, possibly because of the drought here in California. “Hit” is putting it mildly – there will be NO late-harvest desert Chardonnay this Christmas.

    Because the cables are far below the roof, the only way the rats can get to the cables is via a high back wall, which IS accessible via the roof. I tried a rat trap on the wall and found they simply jumped over it. So I put an old mouse trap several inches before the rat trap. That night one jumped, landing right on the rat trap. I left the unfortunate jumper there over night as notification, then disposed of the critter. Apparently rats learn such lessons quickly. So as long as the sequence of traps forces them to jump onto the rat trap, they stay away.

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