When spring finally arrives we are often very anxious to get in the garden to prepare for a summer of blooming flowers and vast expanses of green. One can hardly be blamed for wanting to get in the garden after a long dark and cold winter. However, too early a start on spring cleaning can have negative effects on the insects we rely on for a healthy garden.
Many beneficial insects, such as lady beetles and bumble bees, overwinter in the adult stage. In the fall they seek out shelter under leaf litter or in the thatch that builds up under ornamental grasses. These localities provide extra insulation from the winter's cold. Once the snows melt and the air temperature rises enough to warm to soil both plants and insects begin to emerge from their winter slumber. The timing of who does what and when is largely determined by the temperature.
Plants usually emerge first with the insects emerging only when there is food available. In the case of detritivores (those insects that feed on decaying organic matter), the limiting factor is temperature only. They have plenty of plant material to feed on once the snow clears. They do not have to wait until the green plants are growing or flowering.
Predators will be out and about early in the spring as well. If they feed on detritivores, they will have abundant prey once the snow clears. If, however, they feed on insects that feed on plants, then these species will awaken later, once the plants have already begun to grow and become host to plant-feeding insects. This is the case for lady beetles (also called ladybugs or ladybird beetles). They are generalist predators who feed on soft-bodied insects like aphids. If you disturb lady beetles from their slumber too early, they will wake up and have no food, resulting in them starving to death. Similarly, if you disturb bumble bees and other bees too early, there will not be sufficient flowers for them to collect nectar and pollen.
Therefore, relax, enjoy the early part of spring and let nature take its course. The early risers will benefit from leaf litter and grasses not being removed so they can do their job of recycling, and adding valuable nutrients to your garden. The late sleepers will appreciate not being awakened before there is ample food available, thus ensuring you have pollinators and predators providing their essential services to your garden. There will be plenty of time to spend in the yard come June and July. Leave April and May to our insect friends to get your garden primed and ready for you to enjoy.