What Is The Biggest Contributor to Summer Pests?
Pests come in all shapes and sizes but when improper irrigation and unseasonal rain attributes to their manifestation, that’s another thing. If the truth was known, we can’t do much to our landscape when Mother Nature decides to dump an acre foot of water (325 , 851.427 gallons) on our yard, but it’s another thing if we get sloppy with our irrigation.
Unseasonable torrential rains have ripped through the most unlikely place ever, California. For those of us who live in the mid-west or anywhere east of the Rockies, rain is a way of life. When excess moisture has no place to go it’ll hide right in front of our noses but sometimes we can’t see it!
Today we’ll take a gander where to look for excess water/moisture and the Top 3 ½ Summer Garden Pests that thrive in it.
Where does excess water go?
Soil is made up of sand, silt, clay and organic matter (OM). In a perfect world, the percentages of each would complement each other, making up a divine soil that all plants would like. However, each plant can differ in the soil it loves and depending on where you live, that soil could be awesome (a rich, well-draining soil) or a horrible mess (caliche clay).
Imagine for a moment, a gallon jar of marbles with different colors and sizes. Those will represent sand, silt, clay and OM. Notice how there are gaps between the marbles? Those are air gaps.
Now, since we are still in pretend-mode, fill up that jar with water and watch how it travels past the marbles filling the gaps to capacity. Now, keep filling the jar but don’t stop. Where’s all that excess water going? Probably all over the floor and are you ever in trouble for making a pretend mess.
Rainwater and irrigation water does the same thing to soil as you did with the jar of marbles. There comes a point of saturation that the soil can’t handle any additional moisture.
Some of the soil particles are absorbent and may swell squeezing the air gaps closer to each other, making it difficult for the water to move further into the soil. In the landscape, you end up with puddles, a lake, swamp, stream, or river. At this point, you might open up a new business, an insectarium, because that yard has become a breeding place for the Top 3 ½ Summer Pests.
What are the top summer pests?
1. Mosquitoes
Perhaps the most deadly of all insects in history is the mosquito (aka Skeeter’s) . They are known to spread diseases of biblical proportions resulting in 700,000+ deaths per year. In Western times,Yellow Fever, spread from mosquitoes, has annihilated humans, horses, and birds. In 1999, West Nile Virus was introduced to the U.S. and by 2003 it spread throughout the country which has landed people in the hospital and morgue . Most recently the tenacious Aedes (pronounced “eighties”) mosquito will get 100 million people sick and 40,000 might die annually due to the spreading of Dengue virus spread by the Aedes skeeter.
Fun Fact: A mosquito is attracted to your breath (CO2) which it can detect upwards of a football field away!
That’s the sad part of the mosquito; the happy part is that we can do a lot to slow them down. Before running outside, it’s not a bad idea to lather or spray on some mosquito repellant. There have been leaps and bounds made with organic and natural controls and the good ol’ standby is anything that has DEET as its active ingredient.
Now, what I need you to do is to look closer at your yard more than you’ve ever done before. By the time a mosquito does the wild thing, lays eggs in as little as a ¼” of water, hatches larvae, pupates, then spreads its wings to fly away, it can be as short as two days under the right conditions. The obvious place for this is watery/muddy planter beds, lawns, vegetable gardens, potted plants, and their saucers. The not so obvious are children’s toys, buckets, used tires and wheelbarrows—basically anything that can hold water.
Do whatever you have to do to eliminate standing water. Mosquitos can only travel 2 - 3 miles from where they were hatched. If everyone on your neighborhood were to heed this advice, you just might become as mosquito free as possible.
Serious Skeeter Note: If you have a toy or bucket that has a white film which dried from evaporation it is recommended to destroy them as Aedes mosquito eggs will hibernate in the film and hatch when it gets wet again. Cleaning will not work. It must be destroyed. Plus, most mosquitoes are nocturnal while the Aedes attacks during the day, too.
2. Gnats
Rarely larger than a grain of sand, gnats are a top insect pest. Usually non-biting insects, when you walk into one or a cloud of them from afar a person might think you’ve flipped out because you’ll be swatting what looks like air when in reality they’ve flown into you.
Gnats lay their eggs in anything that’s moist: indoor potted plants, outside planter beds, overwatered lawns, rotting fruit, just to name a few. Have you ever gone grocery shopping to notice you’ve brought home gnats that were tagging along in fruits and veggies? These little pests are more of a nuisance than they are a problem for plants. Some varieties of gnats can actually pollinate ultra-tiny flowers, but in ginormous numbers they can stunt plants and damage roots.
So what’s the deal with gnats attacking humans? Well, our noggin' is oozing with moisture which gnats thrive on. The second you breathe out, they are all over that. It doesn’t take much to make them happy. During that process they find the moisture in your eyes and nose. The easy part of controlling them is by cutting off their food source – moisture.
Let your landscape dry out. Dump out water from container saucers and don’t water houseplants for a short while. Allow everything to dry out and that will disrupt their breeding cycle. If they are out of control outside, spraying organic Neem oil or Spinosad will kill the adult gnats.
3 ½ Slugs/Snails
This gets a 3 ½ because one has a shell (snails) and its cousin (slugs) doesn’t. Both are technically not insects; they are mollusks. For our purposes today, they are garden pest that, like gnats and mosquitos, thrive on moisture. They would rather dine nightly on freshly grown flowers and vegetables, but can also be found munching on ornamentals plants and rotting debris.
Question: Have you ever accidentally stepped on slug which bare feet right between the toes? YUCK!
There are untraditional, organic, and chemical ways of controlling slugs/snails. If you were to call me on the radio, I will always steer you to filling up a mayonnaise jar lid with cheap beer. Slugs/snails will climb inside, get drunk, and then fall of the lid breaking their necks! Actually, they’ll drown because they are attracted to the yeast in the beer but are unable to get out. If you’re a teetotaler like me, you can put a pinch of baking yeast in water and it’ll do the same thing.
Decollate snails (aka Killer Snails) are cone shaped mollusks that you can buy from the nursery. Simply place them in planter beds then they disappear only to eat slugs/snails when they see them. Otherwise their diet is compost and dead leaves. The only thing you have to remember is to not use any kind of slug/snail chemical controls or you’ll kill the decollate snails. Metaldehyde and Methicarb are traditional chemical ways to bait slugs/snails. People usually incorrectly apply it by ‘salting’ their beds when it’s better to put a pile of 8 or 9 granules several feet away from the planter. This draws them to the bait and will put them out of their misery nowhere close to your plants.
Fun Fact: Many years ago, I installed a sod lawn for a client. Every day thereafter, I found snails in the lawn coming from an adjacent patch of Ivy. A new liquid Metaldehyde just came on the market, which I put a bead of between the ivy and new grass. For the next 4 days I collect three 55 - gallon barrels of snails!
An organic approach would be sprinkle a slug/snail bait made from iron phosphate. It can be used around pets so it’s safe and will slowly break down into a fertilizer.
How To Naturally Deter Moisture-Loving Pests:
Speaking of safe, when all is said and done, although we can’t do much about Mother Nature raining on our parade, we can do the safe thing in our landscape by changing our lawn's sprinklers to subsurface irrigation. It's best to get rid of overhead sprinklers and retrofit each plant with subsurface irrigation that will gently place water lower in the soil so it doesn’t sit on top, puddling up, and making it a calling card for the 3 ½ Top Summer Garden Pest and their friends.
Nick Federoff of ThingsGreen.com is a Horticulturalist for CBS|KCAL News & PBS|KLCS TV