This last Tuesday was the autumn equinox and the official first day of fall. The equinox is a special time as day and night, warmth and cold come into balance before the light gives way to the darkening days that take hold for the remainder of the year.
As mornings have a slight chill in the air, the first signs of fall can be seen in the garden. Plants like ‘autumn joy’ sedum, fall crocus and aster come into bloom while midsummer bloomers including coreopsis, coneflower and black-eyed Susan finish flowering.
Berries on shrubs and trees such as mountain ash and pyracantha ripen in earthly tones of red and orange as pine trees interior needles yellow shedding their old growth.
In the vegetable garden, fruit trees are loaded with fruit. Squash, beans, potatoes and other crops are in full harvest. And of course, the first leaves start to change color lighting up our gardens in hues of red, yellow, and orange. It truly is a magical time!
As the heat and rapid growth of summer wane, there is a stillness and sense of completion in the September garden. However, there is still lots to do and enjoy as we cherish these fleeting days on our slow march to winter. To highlight the joys of fall gardening we will post a variety of information in the coming weeks. To get things started below is a checklist of tasks to focus on.
Fall Garden Checklist
- As plants freeze or to make room for fall annuals, remove summer seasonal color such as petunias, zinnias, and snapdragons. Add plants to the compost pile and mulch beds as needed.
- Empty, scrub, and store hanging flower baskets for next year.
- In containers and beds, plant fall annuals such as asters, mums, pansies/violas, and ornamental kale. You can also plant cold hardy evergreen perennials such as juniper, euonymus, heather, kinnikinnik, and center pieces like red stem dogwoods or hollies that can remain in pots though the winter.
- By early October, finish planting hardy trees, perennials, and shrubs. The fall is a great time to plant as the warm days and cool nights are ideal for root growth and establishment.
- As nighttime temperatures drop below freezing, bring cold sensitive plants like geraniums, fuchsia and begonias into the greenhouse or indoors with sufficient light, space, and warmth.
- Towards the middle of October to early November, plant spring blooming bulbs such as daffodils, crocus, hyacinths, tulips and allium. See our upcoming blog post for more information!
Bed Maintenance Tasks
- To slow growth and prepare plants for winter, stop fertilizing annuals, perennials, roses, trees, and shrubs.
- Properly identify and remove invasive weeds before they set seed such as Scotch thistle (Onopordum acanthium), Canada thistle (Cirsium arvense), knapweed (Centaurea spp.), mullein (Verbascum thapsus) and toadflax (Linaria spp.). Remember the old saying: “One-year seeding is 7 years of weeding.” Also, watch for and remove cool season weeds as they germinate.
- Don’t prune the flower heads on ornamental grasses. Leave these for winter interest until heavy snow topples them over.
- Tip back shrubs as needed for shape but wait for renewal shrub pruning until plants are dormant late winter.
- Continue to deadhead (removing the spent flowers) perennials as they go out of flower but leave seed heads on plants that provide food for wildlife such as black eyed Susan and coneflower. As herbaceous perennials (such as daylilies, hostas, and salvia) yellow and go dormant cut plants back to just above the growing crown. Remember not to cut evergreen or semi-evergreen perennials such as basket-of-gold, candy tuft, dianthus, creeping phlox, and lavender. These will remain green for the winter.
- Leaves! Leaves! Leaves! As leaves begin to fall, gather and spread them as mulch or add to the compost pile. Mow up leaves from lawns so not to smother the grass.
- Keep mowing and edging until the grass stops growing. You may have to skip mowing every over week in October as growth slows.
- Fertilize your turf one last time before Halloween. As an organic gardener, there are a variety of products available. This fall fertilization is most important as it stimulates root growth in fall/early winter so that your turf grass will come back green and strong in the spring after winter dormancy.
- To prepare for winter, decrease watering frequencies to established trees and shrubs. Deeply water roses, perennials, and new plants to help prepare root systems for winter.
- Keep watering lawns as needed until hard freezes set in.
- By mid-November in really cold regions, winterize your irrigation by contacting a licensed professional landscaper to use compressed air to blow out your system. By removing residual moisture in your valves, heads, and pipes this helps prevent damage that can occur as the water freezes, thaws and expands during extended periods of hard freezes.
- Pray for winter moisture (i.e. snow and rain) to water the earth and your plants so they don’t succumb to winter dehydration.