The Ecological Landscape Alliance offers these tips from three Eco-Pros about spring clean up in the garden.

The following is a synthesis of the advice offered by Pawel Pielusynski, Brooklyn Bridge Park; Lelsie Duthie, Native Plant Horticulturalist; and Leo Kenney, Ecological Horticulturalist.

• Wait for clean-up until nighttime temperatures are regularly in the 50-55 Fahrenheit range. More larvae and pupae will have had a chance to emerge as adults.
• Cut back old stems but leave 12-18 inches. These stems remain habitat and breeding ground for stem-nesting bees and other insects. Leave the discarded stalks on the ground or cut them into short lengths — and leave on the ground. There may be larvae inside and the stems contribute to soil mulch.
• Use leaves as mulch. Mow them if necessary; most of the insects will have finished overwintering if nighttime temperatures are warm. But leave the leaves whole, if possible. Something beneficial is still living in that leaf litter. (Fireflies lay their eggs there.) Look for places where the whole leaves can be allowed to remain.