My Beneficial Bug Buying Experiment

A few days ago, I wrote about the wasps that are eating many of the beautiful caterpillars that I have seen dining on my plants.

I mentioned that the wasps are seen as “good bugs” by many people, while the caterpillars are seen as “bad bugs.”

Since we don’t use any chemicals that we consider harmful to the environment, we are always looking for alternative means of getting rid of the pests we don’t want and encouraging the critters that we do want.

With that in mind, a few years ago I ordered several kinds of beneficial insects online. I had previously purchased a bag of ladybugs from my favorite local garden center, but they immediately flew away when I released them, so I decided to try a few more insects ….and to better follow the directions this time.

Here is what I learned:

Ladybugs - Both the adult and larval ladybugs help control aphids, scale, mealybugs, spidermites and whiteflies, as well as other insects. The adult female ladybug lays up to 50 eggs per day, usually on the upper side of leaves of infested plants. The eggs hatch into orange and black marked larvae which can consume 400 or so aphids during this 29 day stage of their life. Ladybugs live about 11 months as adults.

Live ladybugs can sometimes be purchased from local garden centers. In many instances, 90 to 95 percent of the ladybugs you release in your garden will immediately fly away. To increase the number of retainees, follow these suggestions: water the site before releasing the ladybugs or release after a rain; release the bugs in the evening, never in the heat of the day; have plenty of their favorite plants in your landscape. Another suggestion is to release only a few ladybugs at a time, over a period of about a week, instead of emptying the entire bag all at once. The rest can be stored in the refrigerator (NOT in an airtight container!) until their release.

The first time I purchased and released live ladybugs, I had the experience that many people do:  they all immediately flew away. But for the purpose of my “beneficial bug buying” experiment, I ordered some that were called Sta-Home Lady Beetles (900 for $13.95) from a popular online source for “Environmentally Responsible Products.” According to their advertisement, their ladybugs are ‘screened to remove parasitized bugs, they are ready to lay eggs, and they are hungry for pests.’

After releasing the ladybugs into my garden, I was quite impressed that many of them stayed around for weeks and even months. I did not do anything to retain them, but I did have a plant that was well infested with aphids. However, I rarely see ladybugs in our yard now so they haven’t seemed to stay around over the years.

Green Lacewings – Many sources cited lacewings as the most effective predators you can buy. They eat aphids, thrips, mealybugs, scale, moth eggs, whiteflies, small caterpillars and mites and are thought to stay around a little better than ladybugs. You can purchase lacewings as eggs, larvae and adults. The larvae are the most voracious form of this insect but it is suggested that they be purchased as eggs and allowed to hatch.    Unlike ladybugs, lacewings should be released during the day. Lacewings are less likely to fly away than ladybugs if you provide the adults with sources for food, such as pollen, nectar and honeydew.

I ordered my lacewings as eggs (1000 for $11.95) but some had already hatched by the time they arrived, I scattered them around my garden, as directed, and never saw them again. Nor did I see any adult lacewings.
However, I have plenty of ants in my gardens and ants eat lacewing eggs and defend aphids from these predators to protect the honeydew that aphids secrete. Therefore, lacewings may not be a good choice if you have too many ants in your plants.

Although I rarely see green lacewings now, I DO see their eggs all the time, so I know they are still around our property doing their job. I’m not sure if this has anything to do with the ones we bought for my bug buying experiement, but I guess it could!

Praying Mantids – Although praying mantids are readily available for purchase, I read that they were of little use as effective pest control. When small, they are excellent soft-bodied insect predators. However, as they get bigger, they indiscriminately eat anything that passes in front of them including honeybees, butterflies and supposedly, hummingbirds. Because of their indiscriminate eating habits and their poor survival rate, I decided not to buy any.

Trichogramma Wasps -These tiny wasps are very popular and very effective Lepidopteron egg parasitoids, which means they are either loved or hated in the garden, depending on whether you like butterflies or not. These wasps reproduce by laying their eggs in the eggs of many Lepidopteron species (butterflies and moths). They are useful for controlling gypsy moths, codling moths, tomato hornworms, cabbage loopers, imported cabbageworms and European corn borers. If you are a butterfly gardener, they will also kill many butterfly species.

The adult wasps lay up to 300 eggs each, into the eggs of 300 soon-to-be destructive caterpillars. Instead of pests hatching out, more tiny wasps hatch out from the pests’ eggs.

The life span of these parasitoids is roughly seven days in their immature stages, then up to 10 days as adults. To get the right species of Trichogramma wasps for your climate and pests, it is recommended that you discuss your needs with the supplier, which I didn’t do. The wasps arrive ready to emerge from host eggs, which are glued to a card. Timing is critical when introducing trichogramma wasps to your garden. Prey eggs have to be available since the wasps can’t parasitize the larvae.

The Trichogramma wasps I ordered came on a small card, which was supposed to have the wasp eggs on it (4000 for $5.75). I could not see them with the naked eye and since I did not have a caterpillar problem in my gardens, I couldn’t really tell whether the wasps emerged and did anything.

I have seen an increasing decline in my butterfly larvae population over the years, which I thought may be related to those wasps. However, the wasps I see are eating the caterpillars themselves and not the eggs, so I think they are a different type of wasp.

So before you spend your money buying beneficial insects, I suggest that you try to lure them to your yard. As with most things in the garden, all it takes is the right habitat.

Related post: Attracting Beneficial Insects for All Natural Pest Control 

National Pollinator Week - June 18-24th

I guess it’s a little apropos that I was so absorbed with the butterflies in my yard (see my last two posts: #1, #2) that I forgot to mention that this week is National Pollinator Week. Or maybe it snuck up on me because it is typically the final week in June (which is next week instead of this week).

In any case, National Pollinator Week is a great time to learn more about the valuable benefits that pollinators play in our gardens and in world-wide food production.

Five years ago, the first Pollinator Week was celebrated with  the unanimous approval of the  U.S. Senate.  Pollinator Week is now an international celebration of the valuable ecosystem services provided by bees, birds, butterflies, bats and beetles.

It is estimated that about 90% of all flowering plants rely on animal pollination (as opposed to wind pollination) and over 200,000 species of animals participate in the pollinating. Without pollinators, many plants would never produce fruit or set seed and many of the foods we eat would no longer be available. As if a world lacking chocolate and coffee wouldn’t be bad enough, wild creatures that rely on pollinated plants for food and shelter could also disappear.

Like so many other species, some pollinators are showing steady population declines. Although the declines in honeybee populations are mainly due to diseases, declines in wild pollinator populations are attributed to habitat loss, competition from invasive species and exposure to pesticides. This is a valuable reminder about why it is important for eco-friendly gardeners to eliminate pesticides.

There are several activities in the area to celebrate Pollinator Week, listed on the events page of the Pollinator Week website. But a visit to any of the local butterfly gardens or to a local beekeeper may be the best way to learn more about these important garden visitors.

And don’t forget that another great way to help protect pollinators is by supporting the Pollinator Plate project.

There are many posts on this blog related to butterflies and hummingbirds, two of my favorite pollinators. You can use the Topic Index at top to find them. Here are a few posts related specifically to pollinators:

• Attracting Pollinators
• 10 Things You Probably Didn’t Know About Honey Bees
• First Rooftop Garden Built for Bees

There is Nothing either good or bad, but thinking makes it so

Most of us have heard the quotation above. It is a quote from Hamlet by William Shakespeare: “There is nothing either good or bad, but thinking makes it so.”

Shakespeare also penned the line “a rose by any other name would smell as sweet” which is proceeded by the line “’Tis but thy name that is my enemy.”

As a gardener, those lines often come to mind when I think of both weeds and bugs.

Weeds, native flowers, wildflowers, flowers. Whether they are welcome or unwelcome is really up to us and how we choose to think of them.

The same, is certainly true of visiting garden critters. Good bug, bad bug, beneficial insect.

For the past week, I’ve been watching an “army” of caterpillars dining on the dill and fennel plants in our garden. Now, “army” wouldn’t be my choice of words to describe caterpillars, but it seems to be the preferred word to use when describing a collection of these crawling critters.

And although  some people would see chomping caterpillars as “bad” bugs, quickly decimating the dill and fennel plants, I love watching the whole process of egg to caterpillar to butterfly and was delighted to go out every morning and watch their progress.

But what started out as an “army” of at least two dozen tiny swallowtail caterpillars soon turned into ten, then seven and now its down to two.

What conquered my “army” of caterpillars? A wasp. The kind of wasp that many people see as a beneficial insect just because they DO dine on caterpillars. So in my garden, this good guy (wasp) has definitely turned into the bad guy.

The irony of the whole thing is, there was a time when I introduced those wasps into my yard.  I'm always trying to find alternatives to using toxic chemicals in my landscape because I know that they can pollute the environment. So to test the effectiveness of purchased beneficial insects I ordered ladybugs, green lacewing larvae and caterpillar-eating wasps. Of course, I was thinking more about getting rid of the caterpillars that I DON'T like, rather than the ones that I do, but I haven't quite figured out a way to train the wasps yet.

I know that neither the caterpillar nor the wasp is bad (or good, for that matter). They are both just doing what they need to do to survive. The Circle of Life, as my husband said.

But the defeat of my beautiful little army by one solitary wasp was a good reminder about gardens and gardening: “There is nothing either good or bad, but thinking makes it so.”

Related posts: Don’t Let the Bugs Bug You
Changing Your Relationship With Weeds

Attracting Beneficial Insects for all Natural Pest Control

I’ve decided to devote my next few posts to chemical free pest control. I could give you a lot of reasons why it isn’t a good idea to use chemicals in a landscape. A HUGE one is that everything you put into your yard has the potential of finding its way into our local waterways, which is the leading cause of non-point source pollution.

But I think the main reason that I am in such a “buggy” mood is because I just bought a new camera and, when in macro mode, it can take photos as close as ½” away. Its really hard for me to kill something after I look that close at its tiny little face.

So for my first post this week, instead of telling you how to get rid of bugs, I am going to tell you how to get MORE bugs to your garden…the beneficial insects that will do some of the dirty work for you in your fight against garden pests.

Many of the insects that visit our gardens provide a benefit. Some of them improve the soil. Others pollinate our plants. But the term “beneficial insect” is probably most often used to describe good  insects that control the bad insects that cause problems in the garden. This definition of ‘beneficial insect’ describes the watchdogs of the gardens – the tiny sentinels that keep those pesky garden intruders such as aphids, mealybugs, scale and whiteflies in check without the use of harmful chemicals. Some of the most popular beneficial insects are ladybugs, green lacewings, parasitic wasps and dragonflies.

The question, of course, is how do we get the beneficial insects to our gardens? And even more important, once they are there, how do we get them to stay?

Before we go any farther, there is one thing that you need to remember: Beneficial insects are just another form of wildlife. So instead of thinking ‘bug’, think of something larger:  Birds, perhaps.

With that in mind, think of the two primary ways that you can get beneficial insects into your garden. You can purchase many varieties from local nurseries and online specialty stores. Or you can try to lure them into your garden.

Bats, hawks and many other forms of wild birds are all excellent at keeping the pest populations down on your property. But what do you think would happen if you could go to a store and buy a large quantity of predatory birds and release them on your property?

First of all, most of them would immediately fly away. And the ones that did manage to stay around may not be well adapted to your area and may become sick or cause problems to the native wildlife.

Now think of the second option. Imagine that you create an environment that the predators find so inviting that they fly in on their own and setup housekeeping. You will attract NATIVE predators that want to dine on the NATIVE insects.

So if luring beneficial insects makes so much more sense, how does one go about doing it?

As with any form of wildlife, if you want to entice beneficial insects to hang around, you must provide for their basic needs: food, water, safe shelter and places to raise their young. If you release any wild creature in your yard without providing these elements, its immediate reaction is going to be to get out of your yard! The same is true of live insects.

Water: Ponds, birdbaths and rain gardens all provide enough drinking water for insects. If you do not have any of these sources on your property, a shallow dish or pan of water filled with pebbles so the insects won’t drown will suffice. Change the water every few days to discourage mosquitoes from breeding.

 Shelter: Leaf litter, mulch and other yard debris provide sources of shelter for beneficial insects. So do stone, driftwood, shells and other natural garden decorations. But in addition to shelter, you must provide for the health and safety of beneficial insects. This means eliminating harmful chemicals and bug zappers from your garden. Both of these items kill as many beneficial insects as they do pests.

Food: This is the most important item that must be present in a garden to encourage beneficial insects to stay. There are two ways in which beneficial insects control other insects. Predators, such as dragonflies and ladybugs, feed directly on their prey. Other beneficial insects are parasites and kill their hosts by laying eggs on or in them. The growing young, in turn, kill the host insect by using it as food. So in theory, if you have pest insects in your yard, you will have food for beneficial insects. However, garden pests are usually not enough to entice beneficial insects to stay. Beneficial insects also require key components found in pollen and nectar plants. Without these plants, beneficial insects cannot survive. If you provide plants that beneficial insects enjoy, you will have a much better chance of attracting and retaining beneficial insects in your garden.

As a general rule, beneficial insects like tiny flowers that offer both pollen and nectar. A variety of plants should be selected that bloom at different times of the year and for best results, intersperse these plants amid your other plants.  Beneficial insects love the tiny, fragrant flowers of many types of herbs and vegetables. If you grow this type of plant, allow some of them to fully bolt and produce flowers.

Although you can buy beneficial insects online and at some local nurseries, I suggest that you try to attract them to your yard, first. As with most things in nature, it is always better to conserve or supplement the beneficial insects already at work in your garden then to try to bring in imports. Also keep in mind that If you introduce purchased beneficials into your yard to control a pest problem, you may find a negative impact on native butterflies, moths, pollinators and other friendly garden residents.

Plants that attract beneficial insects: Alyssum, Angelica, anise, baby’s breath, bee balm, calendula, candytuft, carroway, carrot family, cilantro, clover, coreopsis, coriander, cosmos, daisy, Dill, evening primrose, fennel, feverfew, goldenrod, lavender, lemon balm, lovage, marigold, mint, mustard family, parsley, Queen Anne’s Lace, rue, spearmint, sunflowers, tansy, thyme, yarrow, zinnias and any wildflowers native to your region.

More resources: The Best Plants to Attract Beneficial Insects, Mother Earth News Magazine
Ladybugs: Natures Beautiful Little Killing Machines
How to Attract Beneficial Insects and Animals, Mother Nature Network

Eco-Friendly Tips for the Summer Landscape

I thought this great scarecrow that my friends Jim and Glennie Duke made was a fitting illustration for my first day of summer post.

Jim and Glennie also created the cute scarecrow couple in my post about Scarecrows and Other Natural Bird Control.

For Summer tips, I've chosen some from The University of Maryland Extension Home and Garden Information Center e-newsletter and added links to some of my previous articles on the subjects.

The entire Extension Center Newsletter can be downloaded here, in pdf format.









Tips for Summer Landscape Care
• Follow proper mowing techniques to help your lawn through the dog days of summer.

• For crabgrass and other summer weeds, try eco-friendly options for weed control or try some Zen weeding.

• Mid-August through mid-October is the best time to start new lawns and renovate or overseed existing lawns. Maryland Extension recommends a turf-type tall fescue cultivar at a rate of 4 lbs. of seed per 1,000 sq. ft. of area for overseeding, or 8 lbs. per 1000 sq. ft. for new lawns. If your lawn area contains more than 50% weeds, consider a total lawn renovation. Newly seeded turf must be watered regularly. (HG 102) . Click here to learn more about Selecting Turfgrass. This post on the University of California website will allow you to find more detailed information on each species: Information about Turfgrass Species.

• Keep newly planted trees or shrubs well watered through dry weather this summer. Thoroughly soak the root ball every few days. A 2-3 inch layer of mulch is helpful. Keep mulch away from the trunk or stem.

• Attract beneficial insects to your landscape by planting a wide variety of flowering annuals and perennials that will bloom over the entire growing season. Good choices are plants in the following families: daisy (marigolds, daises, asters, mums), carrot (dill, fennel, anise, yarrow, parsley) and mint (all mints and thymes).

• Slugs are found on all types of flowering plants. Feeding damage ranges from just a few holes to the entire plant stripped of its foliage in a few nights. Slime trails are a definitive sign of slug activity. Trap with shallow pans of yeast added to water or beer, then discard. Diatomaceous earth, sharp sand or ground crab and oyster shell can also be applied around plants as physical barriers.

• Control weeds by laying down entire sections of newspaper covered with straw or last fall’s mulched leaves.

• Cut back herbs through the summer to keep plants bushy and productive. Essential oils are most concentrated right before bloom. Don’t fertilize herbs as it encourages succulent growth and dilutes essential oils.

• It’s time to begin thinking of fall vegetables. Plant broccoli and cauliflower seed in containers the 3rd to 4th week in June for transplanting into the ground mid July through mid August.

• Earthworms are a sign of healthy soil and are normally seen in the greatest numbers in fall and spring. Adding organic matter in the form of composted leaves, manure, grass clippings, etc. will improve soil structure and attract earthworms.

• Select shredded pine bark or hardwood mulches, not wood chips, for use around your home to minimize the possibility of attracting termites. Avoid any mulches that contain chunks of wood.

• Summer is snake mating season, their most active time of year. Snakes are beneficial creatures and should not be harmed. The most likely encountered large snake is the Black Rat Snake. It can grow to be about 5 feet long and is found in both rural and suburban areas.

• Rabbits can be a destructive nuisance in flower and vegetable gardens, feeding on young and tender plants. They can be excluded with a low, 2 ft. high fence that is secured to the ground. You can also repel them with commercial repellents, bloodmeal, or by sprinkling hot pepper flakes around plants. Or, you can just accept them for the great organic weed control that they provide.

• Prevent deer from feeding on garden and landscape plants, by applying a repellent, such as “Deer-Away”, “Liquid Fence”, “Deer-Off”, “Hinder” or “Ro-Pel” to vulnerable plants. Polywire fencing connected to an inexpensive, solar-powered charger can successfully exclude groundhogs and deer.

• As the summer progresses and temperatures rise and rainfall decreases, cool season lawns usually become dormant. Dormancy is a normal plant response causing them to stop growing and turn brown. Established lawns will not die and watering is not recommended. Newly seeded or newly sodded areas will still need watering.

• Late crops of beans, beets, carrots, Swiss chard, and cucumbers can be direct sown through the end of July.

• Bare soil is very prone to erosion from summer thunder storms. Prevent this by covering the soil with mulch, groundcovers, or turf.

• Mosquitoes are always a summer time nuisance at any outside activity. Reduce mosquito populations by eliminating standing water. Change bird bath water frequently, and empty buckets, lids, garden furniture and toys. The Asian tiger mosquito requires very little water for breeding. Back yard ponds stocked with fish or moving water (fountains or filters) should not contribute to a mosquito problem. However, to be certain, B.t. dunks can bin the pond for mosquito control.

• August is frequently dry. Water deeply by allowing water to soak the soil directly underneath and around newly planted trees and shrubs. Check the depth of water penetration into the soil by digging a small hole after watering. Hard-crusted mulch will repel water and needs to be broken up with a rake or hoe to help the rain and irrigation water to penetrate the soil.

• Late August through September is usually a good time to transplant, divide and plant perennials such as daylily, liriope, and Echinacea. Be sure to keep them well watered during dry periods. If hot, dry conditions persist wait to divide your perennials.

• Do not fertilize shade trees, fruit trees or shrubs in late summer. Fertilization in August is very likely to stimulate new growth at a time when plants are beginning to enter dormancy and could result in excessive winter damage.

• Many kinds of interesting invertebrates live in a compost pile including manure worms, centipedes, millipedes, pill bugs, and pseudoscorpions. They are part of the composting ecosystem and should be appreciated, not feared. Do not attempt to spray or otherwise kill these beneficial critters.

• Ruby-throated hummingbirds continue to visit flowers and nectar feeders. Keep nectar feeders clean and change nectar solution frequently during hot weather to prevent spoiling.

Enjoying the Birds and the Bees in Your Own Backyard - Attracting Pollinators

What do flowers, fine chocolates and flavorful coffee have to do with the birds and the bees?

Both chocolate and coffee are two of the 1000+ plants that depend on visits from the birds and the bees, and other pollinators, to help spread the love, or in their case, pollen, from flower to flower. In fact, it is estimated that about 90% of all flowering plants rely on animal pollination (as opposed to wind pollination) and over 200,000 species of animals participate in the pollinating. Without pollinators, many plants would never produce fruit or set seed and many of the foods we eat would no longer be available. As if a world lacking chocolate and coffee wouldn’t be bad enough, wild creatures that rely on pollinated plants for food and shelter could also disappear.

Like so many other species, some pollinators are showing steady population declines. Although the declines in honeybee populations are mainly due to diseases, declines in wild pollinator populations are attributed to habitat loss, competition from invasive species and exposure to pesticides.

Fortunately, we can do our part to correct the problem by inviting the birds and the bees to our own backyards. Simply choosing the right plants and eliminating chemicals in our landscapes will invite more pollinators, which in turn will bring more flowers, more fruit and a new level of enjoyment to a garden filled with colorful, winged wonders.

The most popular pollinators are already some of our favorite garden visitors – butterflies and hummingbirds. Other pollinators include beetles, bees, ants, wasps, moths and even small mammals.

So how do we attract these pollinators? Plant what they love!

To attract more pollinators to your yard, keep these things in mind:

• Choose plants with overlapping bloom times to provide flowers throughout the year
• Select plants with a variety of colors and shapes to attract different pollinators
• Plant in clumps, rather than single plants
• Whenever possible, choose native plants.  Avoid modern hybrids, especially those with “doubled” flowers, as the pollen, nectar, and fragrance is sometimes unwittingly bred out of these plants in exchange for “perfect” blooms
• Include night-blooming flowers for moths and bats.
• Avoid pesticides, even so-called "natural" ones such as Bacillus thuringiensis (Bt). If you must use them, use the most selective and least toxic ones and apply them at night when most pollinators aren't active.

Include some  favorite plant choices for pollinators in your garden (see lists below). And then pull up a lawn chair and treat yourself to a little coffee and chocolate while you enjoy the birds and bees in your own back yard.

For more information:

Creating a Wild Backyard – Hummingbirds, Butterflies & Bees – Maryland Department of Natural Resources

Creating a Wild Backyard – Bees – Maryland Department of Natural Resources

U.S. Forest Service – Celebrating Wildflowers: Pollinators – http://www.fs.fed.us/wildflowers/pollinators/index.shtml

Pollinator Partnership – http://www.pollinator.org/

Pollinator Conservation Resources – Mid-Atlantic Region

Learn More About Pollinators – Chesterfield County, Virginia Cooperative Extension

Green New Years Resolution - More Bare Naked Gardening

I always make a LOT of resolutions each year. It's a great practice for me, and although I don't always keep every single resolution, I do find that having a list helps keep me on track. I make resolutions about money, health, relationships and, of course, about how I want to take care of the planet.


For the coming year, I resolve to practice more BARE NAKED GARDENING!

Be kind to the planet - everything you do in your garden affects all others  
A void overwatering - it's a waste of money and bad for the environment  
Reduce storm water runoff - it pollutes local waterways
Enhance your soil naturally - use organic fertilizers and soil additives Bare naked gardening in DC  
Nix the noxious products- choose eco-friendly options  
Add some mulch - mulch retains moisture while adding nutrients  
Keep a compost pile - it's a valuable and free source of fertilizer  
Encourage beneficials - worms and pollinating insects are good  
Determine your site conditions - work with mother nature, not against her Bare Naked Gardening in DC  
Get outside! - gardening is good for the body and good for the soul.  
Avoid indiscriminate pesticide use - choose eco-friendly options  
Raise your mower blade to 3 inches- you'll have a healthier lawn  
Don't sweep clippings or fertilizer into storm drains- they pollute waterways  
Eliminate weeds by hand pulling, hoeing and spot treating  
Nurture local wildlife - provide food, shelter and safe conditions for local wildlife  
Install rain barrels - rain barrels conserve water and prevent runoff  
Naturalize your landscape - choose native plants  
Grass-cycle - mulch your grass clippings and return them to your yard

Ladybugs: Nature's Beautiful Little Killing Machines

One of the first things we did in our yard when we decided to “go green” was to quit using chemicals. We made that choice for two reasons: to protect the wildlife that visits our yard and to keep from adding any poisons to local groundwater supplies through stormwater runoff.

We don’t have a huge problem with insect pests. For certain pests, we sometimes use products such as insecticidal soap, which we make at home by mixing 2 tablespoons of baby shampoo to a quart of water and then transferring it to a spray bottle that we can spritz as needed.

But our favorite means of controlling pest insects is by letting predatory insects and other forms of wildlife dine on the problem pests.

There are days when dragonflies fill the air, performing beautiful aerial acrobatics as they swoop and dine on flying insects. We’ve put in a small pond near the house to help attract these flying exterminators and they do a great job during the few times a year when we see termites swarming on the edge of our wooded property.

For plant pests, our favorite insect predators are ladybugs.

I’ve loved ladybugs since I was a child. They are beautiful, gentle, almost storybook looking creatures and I would probably welcome them to my garden even if they weren’t beneficial.

But Ladybugs (also known as Ladybird beetles or lady beetles) are voracious predators, both as adults and in larval form. They help control aphids, scale, mealy bugs, spider mites and whiteflies, as well as other insects. Female lady beetles may lay from 20 to more than 1,000 eggs over a one to three month period, starting in spring or early summer. The tiny eggs are yellow & oval shaped and are usually found in clusters of 10-50, near aphid colonies. The eggs take 3-5 days to hatch and the larvae start chomping garden pests as soon as they hatch, consuming up to 400 aphids during this 29-day stage of their life.

Ladybugs live about 11 months as adults and can eat a whopping 5,000 aphids in their lifetime, in addition to the other garden pests they eat. Within a year, there can be as many as 5-6 generations of ladybugs. In the fall, adult ladybugs hibernate in plant litter and crevices, often at the base of a tree, along a fence or under a rock, where they find some protection from cold winter temperatures.

In theory, you’d think that if you have pest insects on your plants that ladybugs might just naturally find them. But that is rarely the case in our yard. Like the elusive hummingbird (another one of our garden favorites) ladybugs never really started to hang around until we made a concerted effort to attract them.

In addition to eating insects, ladybugs also need pollen and nectar to survive. So if you provide the plants that these beneficial insects prefer, you will have a much better chance of attracting and retaining them.

Beneficial insects are said to love tiny, fragrant flowers, especially those of herbs and vegetables. If you grow this type of plant, allow some of them to fully bolt and produce flowers. A variety of plants should be selected that bloom at different times of the year and for best results, these plants should be interspersed amid your other plants.

Plants that attract beneficial insects include: Alyssum, Angelica, anise, baby’s breath, bee balm, calendula, candytuft, caraway, carrot family, cilantro, clover, coreopsis, coriander, cosmos, daisy, Dill, evening primrose, fennel, feverfew, goldenrod, lavender, lemon balm, lovage, marigold, mint, mustard family, parsley, Queen Anne’s Lace, rue, spearmint, sunflowers, tansy, thyme, yarrow, and zinnias. Many of these plants can be grown inexpensively from seed (10 pkgs for $1 at many dollar stores and when on sale at Walgreens).

In addition to choosing plants with flowers to attract the beneficials, I have also heard about using “banker” plants. A banker plant is a plant chosen specifically to attract and host pest insects, which in turn will attract more beneficials.

I first learned about banker plants from Dr. Lance Osborne, a professor of entomology at the University of Florida who explained that “An ideal banker plant system utilizes a pest insect that does not hurt the crop or plant you are trying to protect but attracts the beneficial that will move off that plant and onto the other pests in your garden.”

Dr. Russell F. Mizell, III, another professor of entomology from the University of Florida, said that crape myrtles can be excellent banker plants.

“Crape myrtles attract an aphid which is host specific. In other words, it does not feed on any plants other than crape myrtles. However, the crape myrtle aphid and their sugar-laden honeydew serve as food for twenty or thirty species of beneficial predators as well as countless bees and wasps. Because the [crape myrtle] aphids are not native to the U.S., most of our native predators do not prefer these aphids over the native species. So the predators will leave the crape myrtles periodically to search the surrounding vegetation -- your yard and garden -- for their more preferred prey, your other plant pests, thereby, enhancing natural biological control. To be successful, you have to ignore the sooty mold and the aphids on the crape myrtles.”

Studies by universities and the USDA have shown that spraying plants with artificial insect attractants greatly increases egg laying of beneficial insects. Artificial food sources such as Wheast® are available for purchase from organic garden suppliers. Or you can make your own “fast food” for beneficials by mixing one part whey yeast (or brewer’s yeast) with one part sugar and 10 parts water and spraying the mixture on your plants. Plants should be sprayed when temperatures are below 80F. You extra "bug food" can be stored in a sealed container in the refrigerator for 7-10 days.

It should go without saying that if you want to attract ladybugs, and other beneficial insects, you should eliminate pesticides from your garden. Pesticides will hurt both the ladybugs and the insects that they feed on.

You can also purchase ladybugs at local garden centers and many online sources.

The first time I purchased and released live ladybugs, I had the experience that many people do: they all immediately flew away. This was despite the fact that I followed the suggestions to help retain them, such as watering the site before releasing the ladybugs (or releasing after a rain) and releasing the bugs in the evening, rather than the heat of the day. Another suggestion is to release only a few ladybugs at a time, over a period of about a week, instead of emptying the entire bag all at once. The rest can be stored in the refrigerator (NOT in an airtight container!) until their release. On severely infested plants, you can drape a thin sheet over the plant and release the ladybugs underneath.

I had better luck with Sta-Home Lady Beetles (1 pkg for $13.95 – enough to cover 1000 sq ft.) which I ordered from Gardens Alive, an online source for “Environmentally Responsible Products.” According to their advertisement, their ladybugs are ‘screened to remove parasitized bugs, they are ready to lay eggs, and they are hungry for pests.’ After releasing the ladybugs into my garden, I was quite impressed that many of them stayed around for weeks and even months. I did not do anything special to retain them, but I did have a plant that was well infested with aphids.  

One Note: The Asian Ladybug

There are two types of ladybugs that can be found in our gardens: the native ladybugs species, Hippodamia convergens, and the Asian ladybug, Harmonia axyridis, which was imported into our country at the beginning of the 20^th century to help reduce the populations of tree-killing aphids. If you decide to buy ladybugs, it is best to make sure you are getting the native species.

For more information:

Try Pesticide Alternatives (PDF File)

Where to buy ladybugs in Washington, DC