Snails must be the most well known of all garden pests. In a single evening they can destroy plants, entire beds of seedlings and even your postage. They are especially attracted to succulent plants like spinach and lettuce and low hanging fruit like strawberries and tomatoes.

Not so fast!

A common organic gardening technique suggests making a beer trap.

No, I said BEER trap, not BEAR trap!

This involves using a watertight container – fill it with beer and bury it level with the ground. The snails, alcoholics that they are, are attracted to the beer, fall into the trap and drown.

Are snails really attracted to beer? Or is the trap simply acting as a “gravity trap”? Can I use a cheaper alternative to beer?

In my experiment, I’ll use 3 identical yogurt containers. I will bury them close together and fill them with 3 different liquids: Beer, a beer substitute, and water (the control). If the snails are only caught by the beer container, I’ll know the snails are indeed attracted to beer. The beer substitute will indicate that the snails are actually attracted to sugar, yeast and alcohol. And finally, the water container will tell me if the trap is simply acting as a gravity trap.

Recipe for disaster? Remember to take the cap off

First, the beer substitute.  I’m using a 2L milk container to mix 2 cups of sugar, half a teaspoon of yeast, and the remainder with water. The mix will ferment, release C02 gas, and create alcohol after a day or 2.

Got gas?

Next, the beer trap.

What snail could resist?

And finally, the container with only water.

Every morning I’ll check the snail count in each and remove the dead snails. I’ll top up the mixes as required.

2 Weeks later and the final tally is in…

• Water – No Snails!
• Beer substitute – 4 snails
• Beer – 8 snails and 1 slug

It would seem that beer does indeed attract snails, with 8 snails and a slug caught in the beer trap. The beer substitute wasn’t nearly as successful with only 4 snails caught, most of which were rather small. Finally, the water trap lost out with ZERO snails caught.

So there you have it, the beer trap works… but at what cost?

Other Garden Myths in this series:

• Garden Myths – Ants will not walk over Pennyroyal
• Garden Myths – Vaseline as Horticultural Glue

Organic gardening is becoming very popular among casual gardeners, especially when creating herb or vegetable gardens. I believe the biggest reason for this is the fear of using pesticides on food-growing plants. However, many gardening techniques are bundled under this umbrella term and many of those are very thin on science to support their claims.

I therefore set out to try as many of these techniques as possible and apply some basic experiments to see if the techniques are effective. These experiments are born out of my own need to find solutions to pests and other problems in my own garden, without resolving to pesticides or chemicals that could end up in the food I eat.

So, in the vein of the ever popular TV show Mythbusters, I bring you: Garden Myths

• Garden Myths – Ants will not walk over Pennyroyal
• Garden Myths – Vaseline as Horticultural Glue
• Garden Myths – The Beer Snail Trap

In my last post, Garden Myths – Ants will not walk over Pennyroyal, I tested Pennyroyal as an ant repellent. This week – can Vaseline be used as an alternative to horticultural glue?

Horticultural glue is a sticky substance (yes, I said it) that you apply around a tree’s trunk that prevent ants and other pests from climbing up your trees. Why are ants a problem? Well, ants themselves do not harm plants, but they protect and farm a variety of other pests, including aphids, scale and white flies. This prevents the natural predators of these pests from controlling their numbers.

Ladybugs are a natural predator of aphids and scale insects. Picture blatantly stolen from Wikipedia.

Problem is, horticultural glue is not available in South Africa and it is expensive. Someone suggested I try using Vaseline instead – apparently ants can not walk over the sticky stuff.

When in doubt, lubricate!

For this test, I will need to establish if Vaseline is an effective ant barrier, and if so, how long does it last?

Nice, thick band of the sticky stuff

All dressed up and nowhere to go

Within minutes of applying the Vaseline, it appears that the ants already in my lemon tree are trapped. Ants trying to climb up the tree are stopped in their tracks. Well, looks like we might have a winner. So how long does it last?

Two days later…

After only 2 days, the Vaseline seems to have gone slightly less tacky. The ants seem to have no problem walking over it now, even if it slows them down a little.

Unfortunately, another garden myth busted.

Other Garden Myths in this series:

• Garden Myths – Ants will not walk over Pennyroyal
• Garden Myths – The Beer Snail Trap