One is a beetle, another is an insect. But together they form quite a natural relationship that can be of help to gardeners and farmers who are in constant search of a more sustainable approach to agronomy.
Aphids
Aphids are small sap-sucking insects that are exceptionally good at procreation and spreading at a rapid pace. Aphids are considered to be one of the most destructive insect pests due to their ability to weaken plants and transfer various viruses that tremendously affect plants.
Damage-control is not that easy when aphids are involved. Insecticides are not always effective, especially after aphids developed resistance to some of them. There are some natural enemies against aphids, such as parasitic wasps, crab spiders, different larvae and even fungi. But we want to give special attention to ladybugs.
Ladybugs
Ladybugs (North America) or Ladybirds are a widespread family of small beetles (not the actual bugs). Unlike aphids, they are considered quite useful in the nature due to their appetite for agricultural pests. Besides aphids, they also feast on mites, scale insects and small caterpillars.
However, some species are herbivorous themselves but their impact is considered to be minor. These predatory species are often used as biological control agents, which plays an important part of integrated pest management (IPM) programs often used in farming and gardening.
Ladybug sourcing
You can find many nurseries that sell ladybugs commercially for use in your gardens and small fields. Some ladybugs are reared in insectaries, and some are also wild, usually caught around California where they like to spend the winter months.
It is not recommended to release “non-native” ladybugs to your area to avoid further natural complications. You should consult with nurseries about species that would be a good fit in your environments prior to purchase.
Breading your ladybugs
You can easily breed your own ladybugs instead of purchasing them. There are several simple steps in raising them for the release:
Habitat: You can use a clear plastic container or a glass jar. Make holes for oxygen, place a damp paper towel for humidity, and replace it every couple of days. Keep a stick with some leaves for ladybugs to crawl and lay eggs (They lay eggs on the bottom-side of leaves).
Sourcing: Search and capture the ladybugs with minimal handling; shake the plant to drop them in the jar or use tweezers to lightly grab and place them in the jar. Keep the habitat in an area with shade after capturing the ladybugs.
Feeding: All ladybugs need is their favorite aphids and some water. Place some branches and leafs infested with those insects and mist some water for them to drink.
Maintaining: Check your container daily and remove any dead ladybugs. Poke with a stick if necessary to check for signs of life. Keep the paper towel moist and remove old food particles that are not eaten; old food will rot and grow mold.
Ladybug handling
Once you get your ladybugs purchased, you need to know how to properly handle them before introducing them into their new habitat. You may temporarily store them in the refrigerator for up to 3-4 weeks before final release; beetles left out at room temperature rapidly deteriorate.
Also, ladybugs might get dehydrated, so it’s a good idea to mist them with water before placing them in the refrigerator for storage, making sure not to have any excess water. Make sure not to store them for more than their expiry date stamped onto the label of the bag.
Releasing your ladybugs
Since ladybugs are so hungry for aphids, you need to make sure you have a large aphid population on your plants, enough to keep your ladybugs full and happy. There is no point in releasing them on plants with few aphids. Don't release ladybugs on plants that have been sprayed with insecticides, or it will kill them.
Dusk is a perfect time for ladybugs to be finally released; the environment is not too hot and dry which makes it more favorable then sunny mid-day. You can also mist your plants with water providing a source of water for the ladybugs. Simply place them at the base of plants and they will crawl higher in search of aphids.
Maintaining your ladybugs
Don’t be so disappointed watching your ladybugs fly away. There are several reasons they might not or will not stick around. One of them is a lack of food supply; if you don’t have enough aphids, ladybugs will leave in search of new food sources.
It is also important to provide your ladybugs with certain blossoming herbs and flowers that give them the nectar they need for reproduction. Mint, yarrow, angelica, dill and clover are good choices but almost any shallow blossomed plant (including dandelions) will work.
A good strategy is to purchase a larger quantity of ladybugs and introduce 1/3 to 1/2 of the bag storing the rest in the fridge. This way you can continuously release ladybugs throughout the span of a few weeks and keep re-introducing predators to combat your pest population.
Conclusion
Different researches have demonstrated that ladybugs releases can effectively control aphids but only if properly handled. Inadequate release and poor management may lead to unsatisfactory results. Overall, it is a natural way of controlling insects that is safe for your plants and the whole environment in general.