“I need to protect my garden from squirrels. I want to do container gardening on my deck. I have problems with squirrels eating all my berries and some of my veggies. What is the best way to protect them?” Question fromMelanie of Susquehanna, Pennsylvania
Answer: There are several useful ways that you can implement to keep squirrels from eating your prized fruits and vegetables. Take one or more of these approaches, and even the cleverest squirrels will be thwarted.
Netting and/or caging will keep squirrels away from your berry and vegetable beds and containers.
Motion-sensor water sprayers are an excellent method for repelling small animals, like rabbits and squirrels. The Orbit Yard Enforcer is one model with good reviews.
Dogs and cats also help keep squirrels away, and it’s always nice to have pets.
Most foul-smelling Repellents are a good option for protecting ornamental gardens from squirrels, but not vegetable beds. That’s because poor-smelling repellants can impact the flavor of your produce. Mint and chili pepper sprays, however, reportedly turn squirrels off, so give these a try. They should not negatively impact your home produce unless you directly spray berries and fruits.
For the past 14 years, I have grown my vegetables in a community garden plot, which has provided a real education in plant pests, diseases, and weeds. Why? Because these mega veggie gardens are pest hot spots, and summer is the worst time of year for the beasties. Bad insects always attack my beans, cucumbers, tomatoes, and eggplants–threatening to destroy fruits and foliage, and sometimes spreading disease as they munch and crunch along. I must use every tool in the toolbox to fight them. And, if they beat my crops, I often start them again, if there’s time and the season allows. Sometimes beating pests is just a matter of retooling planting time.
The five most common vegetable garden pests that I battle in mid to late summer are Colorado potato beetles, striped cucumber beetles, flea beetles, Mexican bean beetles, and harlequin cabbage bugs. (Cabbage loopers and squash vine borers are also a problem. Click here to read about cabbage looper control, and click here to read about squash borer control.) Each return year after year with regularity, but some years are worse than others. The severity of the previous winter usually indicates the severity of my pest problems–the milder the winter, the harsher the pest problem.
Last winter was pretty warm, so this summer, the pests are rampant. Here are some ways that I have learned to overcome them.
Colorado Potato Beetle
The surest way to attract Colorado potato beetles to your garden is to plant potatoes, but if you don’t have potatoes, they will go for your tomatoes and eggplant secondarily. (Fortunately, they don’t appear to be attracted to tomatillos.) The fat, striped adult beetles emerge from the soil in late spring to feed on emerging potatoes, and then lay clusters of orange-yellow eggs on leaf undersides. They yield highly destructive little orange larvae that eat foliage nonstop and grow quickly. You can kill the insects at any stage, but it’s easiest to pick off the adults and eggs. (Click here to view the full life cycle of these beetles.) The beetles can complete up to three life cycles in a single season, so once you have them, you generally have to fight them all summer.
These insects are highly resistant to insecticides, so it pays to choose non-chemical methods of control. Time and time again, I’ve found that well-timed cultural control and proper winter cleanup are the best means of battling them. Cultural control is essentially picking off the adults, eggs, and larvae and/or pruning off egg- and larval-covered leaves and branches. I generally smash picked specimens, but you can also drown them in a bucket of water. Beetle picking should start in mid to late spring and continue until all signs of these pests are gone. (To learn everything there is to know about Colorado Potato Beetles, visit potatobeetle.org.)
Spotted and Striped Cucumber Beetles
As their names suggest, striped and spotted cucumber beetles favor cucumbers, but they also attack melon vines. Small, striped or spotted cucumber beetles look so cute and innocent, but they are so destructive. Every year my cucumber crop is a crapshoot. Why? It’s not because of the damage they cause by feeding on plants and fruits. It’s the catastrophic bacterial wilt that they spread from plant to plant. Once cucumber vines get cucumber bacterial wilt, there is no turning back. The leaves will start to show droop, and eventually, whole stems will collapse, and the vine will die.
These pests may have two to three cycles in a season and are next to impossible to control, even with harsh chemical insecticides. Floating row cloth cover can keep them at bay, but it’s a hassle and does not allow pollinators to reach the plants, though some cucumbers are self-pollinating, particularly Beit-Alpha types like ‘Diva’.
Tiny jet-black eggplant flea beetles are the smallest summer pests in this list, but they can devastate an eggplant in a matter of days. They attack many other veggies, like radishes, potatoes, turnips, and spinach, but with less ferocity. The small but numerous insects leave little pockmarks all over a host plant’s leaves. Badly damaged leaves barely function, resulting in poor, weak plants that produce puny fruits.
If you want to grow eggplant, you have to protect them from eggplant flea beetles. There are plenty of insecticides that will kill these insects, but only a few non-chemical cultural practices will stop them. The best method that I have found is protecting plants with summer-weight floating row covers that transmit a lot of sunlight while physically keeping insects from the plants. The key is covering plants early and then securing the row covers at the base, so the tiny beetles cannot crawl beneath them. Holding cover edges down with bricks, pins, and even mulch or compost works. The only caveat is that you may need to hand-pollinate plants for fruit set.
Good fall cleanup of infested crop plants will also keep populations down from year to year. On average, eggplant flea beetles will complete up to four generations in a single season. (Click here to learn more about these pests.)
Harlequin Cabbage Bug
These ornamental stink bugs are the worst enemy of summer kale, broccoli, and other brassicas. They suck the juices from the leaves, causing pockmarks all over them. The most striking destruction I have ever witnessed was with enormous Portuguese kale that I had nurtured to a bold 2′ in height through spring. Once the numerous beetles started to attack in early summer, the plant had no chance.
There are a few management practices that will help stop these bugs. Floating row covers can also be used, as was suggested for the eggplant flea beetles, but harlequin cabbage bugs are big enough to pick off by hand if you have the time and can handle the slightly stinky smell they emit when disturbed. Spraying them off with a jet of water will also help knock them back. Small nymphs are also susceptible to treatment with OMRI Listed®insecticidal soap.
Two to three generations of harlequin cabbage bugs can occur each season. By late summer, they are no longer a problem, so that you can plant your fall cabbages and kales with confidence. (Click here to learn more about these pests.)
Mexican Bean Beetle
Like Colorado potato beetles, it’s the larvae of Mexican bean beetles that do the harshest damage to bean plants. The adults emerge in late spring, but they rarely cause major problems on bean plants until midsummer. The adults are orange, black-spotted beetles that lay clusters of orange-yellow eggs below the leaves, much like the Colorado potato beetle. The unusual larvae are fuzzy, bright yellow, and devastate leaves as they feed along the leaf bottoms.
You can control these pests as you would Colorado potato beetles with one exception – destructive harvesting. Destructive harvesting is the harvest and total removal of infested plants from the garden. After picking all the beans from an infested plant, the whole plants should be pulled, bagged, and taken far from your garden. (Click here to view a YouTube video from the University of Maryland about destructive harvesting.) Beans can be replanted as late as mid-August for early fall harvest.
In general, regular weeding, good plant care, and excellent garden clean up, in summer and fall, will help keep pest populations down. Clean the ground of all leaf litter and weeds as needed, and amend the soil with top-quality amendments for vegetables, such as Black Gold® Garden Compost Blend and Garden Soil, and your plants will be more robust to resist the many garden pests that threaten to destroy them.
“What are your best tips for natural pesticides?” Question from Jacquelyn O’Neil
Answer: It depends on the pest. Generally, we recommend purchasing OMRI Listed products approved for organic gardening. But, we also advocate managing pests through IPM (integrated pest management) to keep populations down without the need for harsh chemicals. Integrated pest management employs a variety of tactical techniques for pest control (see infographic below). Monitoring plants, keeping them in good health, and catching pest problems early on will stop pests before they take over.
“How do I keep fire ants OUT of my raised beds? I’m in Texas, and those buggers are devastating! I hate to poison my food … any advice would be appreciated.” Question from Amy of Terrell, Texas
Answer: The red fire ant (Solenopsis invicta) is an introduced species that’s a painful problem down South, and gardeners with fire ant problems really pay the price. Thankfully, there are organic ways to manage them.
About Fire Ants
Let’s start with an overview of these pests. Fire ants create large mounds that can reach a foot and a half in height. A big colony may contain up to 200,000 worker ants and queens can lay up to 800 eggs a day. These pests thrive in southern climates and start causing troubles as soon as the soil warms up in spring. They are small, brownish orange, and have painful, venom-injected stings that hurt like fire. They like to feed on young plants and seeds, so they are attracted to gardens.
Organic Fire Ant Control
If you know where they are nesting in your raised bed, start with this simple method as early in the season as possible, before you start planting. Pour boiling water over their nests, being sure to cover the full nest area deeply. This will immediately kill nests in your beds.
Once you have weeded and turned your beds for the season, spray any ants you see with OMRI Listed spinosad, a natural bacterium that is toxic to insects like ants and approved for organic gardening. You can also buy spinosad ant bait traps for your garden, which won’t harm other insects. Follow the manufacturer’s instructions.
Bait traps that container borax are another option. Borax is a natural ingredient that is non-toxic to us. TERRO® Liquid Ant Baits work very well.
If more colonies appear, you can also cover them with diatomaceous earth (food grade). This has been proven to ward off ant colonies naturally. It also would not hurt to put rings of diatomaceous earth around your favorite plants.
Finally, another safe spray to use that’s effective in repelling fire ants is D-limonene (Orange Guard). It is OMRI Listed for organic gardening and is made from the extract of citrus peels. It really keeps ants away. Follow the manufacturer’s application guidelines.
Tomato hornworms arrive at night as gossamer-winged moths that lay their eggs on your carefully cultivated tomatoes. Hatchlings quickly grow to enormous green caterpillars that can decimate a plant overnight.
Inspect new growth daily for these voracious caterpillars. Hand pick them promptly and discard before they feed on the fruit itself.
Another option is to spray the plants with BT (Bacillus thuringiensis). This safe, non toxic, control is approved for organic gardening. Once BT is on the leaves, worms eat it and get a fatal belly ache. This natural spray is one of the greatest success stories in organic horticulture. You’ll find it in garden centers and home improvement stores wherever Black Gold products are sold.