Almost all of the ladybugs will leave, but 5% to 10% will stay and do their job on aphids.
It helps to have readily available water near where they are released, some experts suggest watering the yard the night before you release.
An average ladybug purchase for your yard should be about 3,000 ladybugs for about a quarter of an acre.
And because of aphid breeding cycles, some experts say a second spreading of ladybugs may be necessary fairly soon after the first.
To order ladybugs, the best bet would be a place that offers a wide variety of gardening products.