Perennial plant care is important as we enter late fall. It is time to give perennials the care they need to make a successful return in the spring. It is natural to watch these plants die each year, but dying too soon can mean they won’t be strong enough to go dormant and come back next year. Below are seven perennial plant care tips to ensure your perennials are dormant and not dead.
Fall Perennial Plant Care Tips
#1 Water
If your perennials are dead, stop watering them. We may think they need help with water even after their natural cycle of living has passed, however, continuing to water a plant that is dead will promote rot or fungal growth in the soil.
However, if your perennials are still alive, continue to water them until the temps drop below 40 degrees. The amount of water you need to apply will depend on the type of soil you have, but you need to water until the top six to nine inches of soil under your plants feels wet. This will help your plants avoid winter kill. The only true way to know how moist the ground is after watering or rain is just to dig out around and feel the soil.
#2 Weeding
The amount and regularity of weeding will certainly decrease in fall, however, it is still important to enter winter weed-free. Allowing the weed seeds to go dormant in your beds will wreak havoc for your spring beds.
#3 Cutting Back Plants
This technique depends on what the plant is. Some plants will need to be cut back right now, and some will need to wait until spring.
Always prune back ANY perennial plants with disease and insect infestations. These conditions don’t clear up over the winter, they worsen. Take the time to properly eliminate them from your garden and throw them away in the trash. Never risk keeping them on your property through compost or any other means.
According to the Farmer’s Almanac, technically, very few plants MUST be cut down in the fall. And never rush to cut things down; hold off until after several hard frosts. Even if the flowers or leaves are dead, the roots reclaim energy from the dying plant for healthy growth in the spring. This list includes:
- Evergreen perennials such as epimediums, hellebores, heucheras, hardy geraniums, dianthus, moss phlox, and euphorbias
- Candytuft, primulas, hens & chicks, heaths, and heathers (considered evergreen), pulmonaria and Penstemons just need tidying in the Spring.
- Garden mums, Anise Hyssop, Red-Hot Poker, Montauk Daisy-
Leave the foliage. It’s important to protect the root crowns over winter. Cutting back the plants severely will simulate late new growth, which will be very susceptible to winter kill.
Perennials to cut include:
- Artemisia
- Bearded iris*
- Bee balm
- Campanula
- Catmint
- Clematis
- Columbine
- Coreopsis
- Delphinium
- Daylily
- Hardy geranium
- Hosta*
- Peony*
- Phlox*
- Salvia
- Shasta Daisy
- Sunflower
- Veronica
- Yarrow
*** Specifically recommended to cut in fall. Others can be, but not necessary.
#4 Divide & Replant
If the plant is older than three years, it is considered mature. Mature perennials need to be divided to keep them healthy so they don’t outgrow the space you’ve given them and start to die off. Cut back foliage before moving so the plant can focus its energy on root growth, not maintaining green growth. Make sure the new place you are moving the plants to follows the correct light and soil requirements.
#5 Move Plants
If you have plants that have been in the same location and don’t flower or live up to their true potential, move them to a spot that will serve them well. Lighting is so important for their conditions and if they are underperforming, they most likely don’t have the correct lighting. Try a new place and see what happens. If they are mature enough and you move them with care they will recover and grow in the spring.
#6 Collect Seeds
Now that your flowering perennials have developed seed heads, cut them and let them dry out. Once dry, you can pull the seeds and store them to plant next year. If your perennial is thriving in your soil and conditions keep that energy going by planting new ones in new spaces.
#7 Boost Nutrients
Topdress with compost and Add 1-2 layers of loose organic mulch to your plants to give them the energy they need to overwinter. Barley straw or spruce branches are great options to blanket the plants. Loose organic mulch is necessary to not trap water in and cause rot. Use whatever organic mulch you have on hand, as long as it can be easily removed in spring when the soil warms.
Don’t let fall pass by without perennial plant care and proper preparation for spring. Now is also a great time to add those bulbs you will see emerge first in your gardens. Take the time to follow this chore list to have an amazing spring.
This article about perennial plant care was written for Hobby Farms magazine. Click here to subscribe.
