It’s August and everybody’s vegetable gardens crank out delicious organic food. Yum-oh! But sometimes gardeners find holes in the middle of the leaves of their vegetable crops. Large holes. Many of them. Who’s the culprit? Caterpillars? Grasshoppers? Beetles?  Or maybe snails!

Snails and slugs both glide through your garden on a ribbon of slime, the shiny, sparkly stuff the snail in the photo above is leaving behind. At bottom left you can see the slime glistening on the ground. These animals are mollusks, related to oysters, clams, and octopus.

A trail of dried slime across the large hole in this green pepper is the definitive clue. A snail or slug definitely made this hole. Anytime you find holes in the leaves or fruit of your vegetable plants look for slime. Slime, this incontrovertible evidence tells you who to blame. And then you know how to fix it.

If you catch the buggers red-handed in the act of destroying your produce you don’t even have to search for evidence. This slug has just devoured the side of a friend’s tomato. Yuk!

But often, you can’t catch them in the act because they hide in the heat of the day. They come out at night, on overcast days, during rain storms, or when the sprinklers come on. They like it cool and wet and they hide under boards and pots – in any cool, shady, damp place where they can survive the mid-day sun and heat.

You can go out into the garden at night with a flashlight and hand pick snails easily. Just pick them up by the shell put them in a brown paper bag. Then you can step on it to crush the critters and bury it in your compost. Slugs, however, have no shells and are too slimy to pick up. Because slugs and snails hide during the day you can also make traps for them and that way you don’t have to go out at night with a flashlight. Put upside-down flower pots around your garden. They’ll hide inside them where you can easily harvest and destroy them in daytime comfort.

Iron phosphate controls these mollusks in the garden. You’ll find it under the brand name Sluggo. Iron phosphate is not toxic to pets, children, or birds. It also has no effect on insects. It kills mollusks and only mollusks. Slugs and snails eat it and they die.

 Older style, toxic, non-organic slug bait uses a poison called metaldehyde. Metaldehyde is poisonous to your pets, your kids, and wildlife. Avoid it.

 Some people swear by beer to kill slugs and snails. You’re supposed to put a shallow bowl of beer out in the garden, the slugs and snails are attracted by the odor, crawl into the beer and drown. Maybe I just don’t do it right but it’s never worked for me. 

True bugs. Forewings cover half of the abdomen (aka backs) of true bugs. They are in the order Hemiptera, which means half wing. Many other insects are often called bugs, the lady bug for example, which is actually a beetle (a lady beetle). But the only actual bugs are insects in the order Hemiptera.

 All of the true bugs have piercing-sucking mouthparts like hypodermic needles. The bugs that damage our vegetable gardens are ones like stink bugs, squash bugs, harlequin bugs, and tarnished plant bugs. But there are also good bugs, beneficial predators, like minute pirate bugs, that use their needle-like mouth to stab other insects and suck the life out of them. Aside from the bugs you find in your garden there are also bugs like bed bugs and kissing bugs, ones that feed on us humans by sucking our blood.

This green stink bug has its needle-like mouth parts inserted into a flower bud and is busy sucking nutrients out of the plant. You can clearly see that the hard forewings (green with yellow dots) only cover half the bug’s back. The membranous hindwings stick out from underneath the forewings and are easily visible to the naked eye. Stink bug feeding leaves Yellow spots of damaged tissue on developing fruits are the tell-tale clue that stink bugs leave behind.

This insect is a spotted asparagus beetle, not a bug and not a lady beetle. Like all beetles, the hard, colorful forewings (red with black spots in this example) completely cover the abdomen and the membranous hindwings are not visible. Beetles have chewing mouthparts, unlike bugs. This pest lays eggs on asparagus plants, and its larvae eats the asparagus berries.

All of the true bugs have incomplete metamorphosis where their babies (nymphs) look like the adults but without wings. The bug nymph shown here on an asparagus plant has very rudimentary wings and strongly resembles the adult bug. When it reaches maturity it will have well developed wings like the green stink bug in the first photo shown above.

The squash bug feeds on squash plants and their relatives. It, like the stink bug, is a true bug. The adults and the babies (nymphs) stick their sharp little beaks into the leaves and suck out the nutritious sap. They can seriously damage your summer and winter squash, and pumpkins, but they will also feed to a lesser extent on any other member of the cucurbit family. The nymphs look a bit like gigantic gray aphids clustered on the undersides of the leaves. When they reach adulthood they have well developed wings and are swift flyers.

In contrast to insects that have incomplete metamorphosis, those that have complete metamorphosis, like butterflies, have babies (larvae) which do not look anything like the adult. The butterfly larva is a caterpillar, a very different creature from the adult. The fly larva is a maggot, also very different from the adult.

 Effective organic controls for pesky true bugs in the vegetable garden include hand-picking where you grab them and dump them into a jar of soapy water. Insecticidal soap is also safe and easy to use. Just be sure that the bug you spray is actually a pest and not a beneficial insect because the soap will kill pests and beneficials alike. If you are plagued by bugs in your vegetable garden this year, think about putting up some row covers next year to exclude the bugs completely.

 Be careful and think twice before using any chemicals to control insects in your vegetable garden. Remember, you’re growing food that you intend to eat. Never spray your food with poison. 

On a tour of secret gardens in Santa Fe, New Mexico, Kathryn and I peek behind adobe walls for tantalizing glimpses of hidden treasures. Organized by the Santa Fe Botanical Gardens, the tour provides access to several small urban gardens not normally visible to passersby.

A beautifully sophisticated yet rustic fence made of reddish twigs defines the boundary between the garden and the natural environment beyond. This very low maintenance garden, features a beautiful mix of native and exotic plant materials all well adapted to local climate conditions and low rainfall. This is a xeriscape garden. Many people think that a xeriscape consists of a cactus and a couple of rocks surrounded by gravel. Obviously, a xeriscape can be much more than that.

In the beautifully designed private garden of the Richardson home an aesthetically appealing yet functional patio provides a transition between home and garden. This garden places all higher maintenance plantings needing supplemental water within the privacy of the backyard. Kathryn and I designed this garden several years ago.

A Montmorency pie cherry tree and a dwarf peach tree provide fresh fruit in season. The fruit trees are adjacent to the patio in the photo above.

The Richardson home also features a small section of the backyard garden devoted to vegetables such as tomatoes and chili peppers. Blue Penstemon strictus, and yellow Aquilegia chrysantha (yellow columbine) are native wildflowers mixed in with the vegetables.

In the front yard of the Richardson home we see a water conserving xeriscape of native wildflowers, shrubs, and succulents in dramatic contrast to the lush greenness of the private backyard. This portion of the garden faces south and is exposed to the intense heat of full desert sun. The function of the dry streambed is to direct and control excess rainwater from summer thunderstorms.

One aspect of gardening in the high desert of New Mexico is that most of the rainfall occurs during the “monsoon season” in the summertime. Snow in winter also provides some water, but most of the water arrives in torrential summer thunderstorms. All the precipitation (snow, hail, rain) that runs off the roof of the house is captured by downspouts and fed into cisterns which store the water in this garden. An extensive drip-trickle system distributes the water to organically grown vegetables.

Another water management technique is the sunken garden shown here. The rainwater and snowmelt which runs off of impervious surfaces such as the roof of the house is directed into these pit gardens which are sunken well below grade. A Russian olive tree rooted in the bottom of the pit shades the garden and provides a moist, shady microclimate for the plants surrounding it.

This adobe wall and dramatic blue gate provide access to a small urban garden featuring permeable paving using flagstones and creeping thyme. Permeable paving allows precipitation to percolate into groundwater without being shunted off into municipal stormwater drainage systems.