|
Perennial
|
What to do with it
|
Why?
|
| Achillea (Yarrow) |
Cut back early fall |
New growth will start before heavy frost getting a head start for next season |
| Aquilegia (Columbine) |
Remove damaged leaves (leaf miner) and debris from plant base |
Plants can harbour miner nymphs over winter and debris can collect fungus |
| Ascelpias (Butterfly Weed) |
Cut back in spring |
Foliage provides winter protection |
| Aster |
Cut back in late fall/early winter after flowers have died |
To maintain vigour and flower quality (you can also divide them every few years in the spring) |
| Brunnera |
Remove dying foliage in winter |
Foliage rots in winter leaving a messy spring clean up |
| Buddleia (Butterfly Bush) |
Cut back to ground every spring |
Blooms on new wood – cutting back to ground provides only new wood leaving you with many flowers |
| Coreopsis (Tickseed) |
Deadhead throughout blooming season to encourage new blooms;prune back dying plant to encourage new growth |
Seeds heads provide birds with winter food |
| Delphinium |
Cut stalks to the ground when finished blooming |
You may get a second bloom before winter hits; if you do, cut that back before winter |
| Dicentra (Bleeding Hearts) |
Nothing required |
Plant will die back completely mid-summer/early fall |
| Digitalis (Foxglove) |
Remove central flower stalk after it has finished blooming; remove dead leaves and spikes in the spring |
Encourages side shoots and more flowers |
| Echinacea (Coneflower) |
Cut down in spring |
Stems provide winter interest |
| Eupatorium (Joe Pye Weed) |
Cut back after frost has killed foliage or in spring before plant starts to grow |
You don’t want to cut this plant while it isn’t dormant |
| Gaillardia x Grandiflora (Blanket Flower) |
Cut back spent stems |
Improves general hardiness |
| Hemerocallis (Daylily) |
Cut back in fall |
Winter will leave you with a messy mush to clean up in the spring |
| Heuchera (Coral Bells) |
Cut back in spring |
Foliage provides winter protection |
| Hosta |
Cut back flower stems once flowers have finished (collect seeds if you desire); cut back leaves before heavy frost |
Removing flower stalks will force energy into root and leaf growth; frost and cold damages leaves leaving them mushy in spring and can harbour diseases |
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| Bearded Iris |
Cut back after heavy frost |
Foliage provides protection for fungal diseases |
| Lavendar |
Fall – well before danger of frostSpring – after flowers have been spent |
You do not want to expose the old growth to frost or freezing temperatures |
| (Leucanthemum) Shasta Daisy |
Cut stems back to ground after flowers are finished |
Harbour slugs, earwigs, aphids, and leaf spot diseases |
| Ligularia |
Cut back before frost |
Frost leaves foliage a mushy mess |
| Lupin |
Cut back damaged foliage in spring |
Encourage new growth, and protects plant through winter |
| Malva alcea (Hollyhock) |
Cut back in fall |
Tall stems will break in winter and foliage will become mushy in spring |
| Monarda (Beebalm) |
Cut back in fall unless mildew has taken over then cut earlier |
Foliage harbours mildews |
| Paeonia (Peony) |
Remove golden coloured foliage after first heavy frost |
Foliage harbours mildew and plant needs cold to set buds |
| Phlox paniculata (Phlox) |
Cut back heavily and destroy foliage in fall |
Extremely prone to mildew problems – destroy foliage to prevent more next year |
| Polygonatum (Solomon’s Seal) |
Leave alone or prune back tall stems |
Foliage falls after frost, stems can provide winter interest if you leave them |
| Primrose |
Prune top foliage in late fall or early spring; remove dead foliage in spring |
Tops will die back here as they are not likely to overwinter very well |
| Rudebeckia (Black-Eyed Susan) |
Cut down in spring |
Stems provide winter interest |
| Sedum |
Can be pruned in early spring before new foliage begins to grow |
Tall varieties provide winter interest |
| Sempervivum (Hens and Chicks) |
No need to prune but remove hens or chicks as area becomes crowded |
Overcrowding creates increased competition for water and nutrients |
| Veronica (Speedwell) |
Prune to the ground in fall |
Plant will rot throughout winter leaving a messy spring clean up |
