perennial overwintering suggestions letterhead
TRANSCRIPT
McKay Nursery’s Suggestions:
Handling established perennials that we grow & how to treat them for winter Amsonia/Blue Star – cut back fall or spring Aster – cut back fall or spring Astilbe – leave up for fall if you like to see the dried flower heads, or cut back fall or spring Butterfly Weed – cut back fall or spring Beebalm – trim to ground in fall and remove all leaves. Bleeding Heart – pull off dried leaves and stems after frost kills down. Brunnera – pull off dried foliage after frost kills it (prevents any leaf disease from over wintering on plants) Butteryfly Bush (a woody ornamental that is treated as a perennial here) – cut back in spring only Caryopteris (a woody ornamental that is treated as a perennial here) – trim back in spring only Catmint – cut back fall or spring Columbine – pull off dried foliage after frost kills it in either fall or early spring. Coneflower – leave seed heads up to feed birds, or fall or spring cut back Coreopsis – leave up for fall and cut back in spring only Daylily – cut back and pull off all foliage in fall (prevents any leaf disease from over wintering on plants or rodents from building in the old leaves) Fern – leave up for fall, cut back in spring Geranium – cut back in fall or spring Goldenrod-‐-‐leave up for winter interest, cut back either fall or spring Grasses – please leave all up for fall and don't cut back until spring, enjoy all winter. Heuchera (Coral Bells) and Heucherella – best left alone until spring, then in spring pull off only dried leaves, don't cut way back. Hosta – pull off old foliage after frost kills the leaves in fall, but wait until dried and it can be pulled and you don’t have to cut it Iris – cut back in fall or spring Jacob’s Ladder – cut back in fall or spring Ladysmantle – cut back fall or spring Lamium/Deadnettle – lightly rake off in spring Liatris /Blazing Star – cut back fall or spring Lungwort – cut back fall or spring Peony – cut back in fall very close to the ground and remove all stems and leaves Phlox – cut back in fall and remove all old foliage (prevents any leaf disease from over wintering on plants). Rudbeckia – cut back in fall or spring (the seed heads are great little bird feeders, but if they had diseased foliage, it’s best to cut off in fall and remove in fall) Russian Sage – cut back in spring Salvia– cut back fall or spring Sedum – cut back in fall or spring (look great in winter if you leave the taller varieties up)
Shasta Daisy – cut back fall or spring Thyme (Creeping Thyme is what we grow) – leave alone to spring then rake gently Veronica – cut back in fall or spring Woadwaxen – cut back in spring like you would a Spiraea Yarrow – Cut back fall or spring I hope that answers any questions you might have. Some people like to go out and just cut everything to the ground. When you do that, you have nothing to look at all winter long (and winter can be long in our area). Why not leave some of these plants alone and enjoy their dormant, spent flower heads or foliage as they sculpt the snow and add tons of winter interest to the landscape? As with all perennials, it is always best to clean up any foliage that was diseased this past growing season as that will help eliminate re-‐infection next spring. Perennials love a fresh application of mulch in fall, as do most deciduous shrubs as well. If you are growing tender perennials in your yard, be sure and give those plants a few evergreen boughs or a covering of marsh hay after the ground has started to freeze to keep the ground frozen on those items all winter long. Freezing and thawing of perennials can cause them to start growing before they really should, and then when they freeze again, it can cause damage. The evergreen boughs or hay will prevent the freezing or thawing, and will prevent the damage. Newly planted perennials (especially newly planted in the fall) really need to be mulched very well when planted around the plants, and then also mulched with evergreen boughs or marsh hay to prevent these plants from being heaved out of the ground by that freezing and thawing process. This is a necessary step to ensure good rooting in fall and to help them best over winter. That is the reason we need you to stop doing installations of perennials by the end of October – so they have a chance to root in before the ground freezes. Fall cut back should not happen until several killing frosts have helped the plants to go dormant, and in spring please cut back just before the new growth begins. If you have any specific questions, please feel free to call or e-‐mail. Thank you, McKay Nursery Company www.mckaynursery.com 800.236.4242