Last autumn, we gave ourselves permission to skip the “fall cleanup” for a good reason. Leaving perennial stalks and foliage provides a habitat for overwintering pupae or hibernating adult beneficial insects, such as native bees, lacewings and parasitic wasps. Also, the fallen leaves can be a great winter mulch. The question I’m asking myself now is… when is it okay to begin the spring cleanup, and what should I not disturb?
The naturalists are telling us to wait until we are well into an extended stretch of 50+ degree temps before cutting back stalks. Arghh!! Here in New England that could be mid-May! I don’t think this wait needs to be a blanket rule. Every garden situation is different.
I noticed during the March garden inspection that the Hellebores were showing signs of fungal problems from leaf spot, downy mildew and gray mold, especially on the old foliage, no doubt from being buried under wet leaves. Note: most of our Hellebores are planted in the garden under our ancient swamp white oak tree. In this case, the blanket of wet oak leaves was not helping. I didn’t want the emerging flower shoots to succumb to fungal diseases, of course, so the leaves were removed and the stems cut back.
In a different garden area, a carpet of fallen leaves from a Katsura Japanese Maple wasn’t causing any problems that I could see. The Snowdrops and Crocus pushed through early on, and the Corydalis solida are not having any problems. My take on this … the smaller, fine textured foliage of the Japanese maple is allowing more aeration under their cover. I suspect that I won’t have a problem leaving things be, for now. I will wait to cut the stems of nearby Japanese Mint Shrub, Leucosceptrum japonicum. However, I did cut back the Epimedium foliage so we wouldn’t have to look at the fresh new flowers shrouded among old brown leaf stems.
Our sunny pollinator display beds presented more of a problem…many plants in this bed grow tall, i.e. Silphium, Eupatorium, Helianthus, Rudbeckia, and their split and broken stems were scattered at all angles…the dilemma being that this is pollinator garden after all, but it was such a tangle! I decided to whack down the stalks, but made sure to leave stems with praying mantis egg sacks which of course I could see. I placed the cut stems in a pile about 20 yards away at the edge of our woodland near the compost piles. Hopefully any larva or emerging adults will realize they are close to their host plants.
This year is going to be a study on how this partial spring cleanup plays out. Will I even notice the fallen leaves once summer comes and plants are flourishing? (Probably not. ) Will I still see all the beneficial insects that have found refuge in our gardens in past years? I think so, but it will be a year to pay attention.
What approaches are you taking to have a happy garden as well as preserve a healthy habitat for our beneficial wildlife? Please share.