Fall. When the morning air turns crisp and cool and the leaves begin to float softly to the ground. Not only is it my favorite season, there are many maintenance tasks to be accomplished in the landscape. The info below includes tips on what I have found are the most important and useful tasks- so get out there, have fun with it, and enjoy the autumn weather!
- Early October: It is a good idea to winterize your irrigation system and blow out the lines. Many landscape maintenance companies will provide this service for less than $50, or it is pretty simple to do it yourself.
- October 15th: Don’t plant any grasses or perennials after this date. Many of them won’t survive, and you will have much better luck in the spring.
- November 1st: Don’t plant any evergreens (especially trees) after this date. Some deciduous trees and large deciduous shrubs can be planted later if they are balled and burlapped (B&B), but I would recommend waiting until spring when you’ll have much better success.
Trees and Shrubs
- Prune trees and shrubs to remove dead branches or to control their size. Fall is the best time to do this for the health of the plants. Consider consulting with an arborist before any major pruning on trees, or at least do a little research on techniques. When pruning shrubs, always try to maintain the natural size and growth habit of the species- Avoid over-pruning or sculpting unnatural shapes, unless you are creating a specific look such as a hedge. Instead of using power shears to lap off shrubs on a straight line, consider using hand pruners to thin the interior branches to maintain a healthier more natural look.
- Remember to check soil moisture, and water if needed. Even though you may have your irrigation system shut down for the year, fall often brings some warm, windy days that can really dry things out. Pay special attention to anything that was just planted this year.
- Make sure you have plenty of mulch around trees and shrubs- this helps maintain moisture and keeps the soil from drying out over the winter.
Perennials and Ornamental Grasses
- Prepare tender and semi-hardy perennials and shrubs for the upcoming cold winter. I like to let a few of the fallen leaves that tend to build up around the bases of these plants remain there for the winter- they will provide insulation around the base of the plant from the cold. This also saves you some leaf cleanup now that you can do in the early spring. If necessary, place additional wood mulch around the base of these plants for more insulation- pay particular attention to areas with northern exposure.
- Leave spent stems and seed heads on grasses and perennials until spring, to enjoy their winter beauty and to provide cover for birds and wildlife. Or, if you must have a neater look you can cut them back now, to a height of about 6-8″ off of the ground.
- Dividing: Some plants can be divided in the fall and replanted in other areas. Other species don’t like the fall division/planting though, and I think that spring is a much better time to do it. If you decide to divide, remember to water the plants well for a couple of weeks.
- Rake those leaves! If left on the lawn they can smother it and cause issues such as mold and fungus.
- Consider aerating your lawn. Aeration allows greater movement of water, fertilizer, and air which stimulates healthy turf. Aerating also increases the speed of decomposition of the grass clippings and enhances deep root growth. Compacted soil especially benefits from core aerating.
- You may want to fertilize your lawn or use a “weed and feed” type light pre-emergent herbicide in the fall for maximum growth the following spring. Don’t over do it though, because fertilizer and herbicide can wash off of your lawn and the runoff can be harmful to water supplies and wildlife.
- Assess the size and configuration of your lawn, and how much water you used this year to keep it green (or, brown?). Consult with a landscape architect about how you can redesign your landscape to make it more attractive, sustainable, and functional.
Fall Weather Considerations
- The days are getting shorter and the weather is getting cooler. Keep an eye on the amount of precipitation we are getting- Fall can have extremes of hot and cold, dry and wet. Be observant. If you have heavy rain for a couple of days then turn off the sprinklers for a week or so to compensate. And if you have several days of warm, sunny weather then your landscape will certainly appreciate an extra drink.
- Disconnect and drain hoses, but keep a hose handy for winter watering. I also like to wrap insulation or put insulated covers over the exterior faucets as an added protection from freeze damage (I once had a pipe freeze and break UNDER my porch, and had to take apart the porch to fix it!).
- Collecting seed: Stop deadheading late in the year and allow the seedheads to dry on the plant. Then you can collect the dried seeds to plant next spring. Store them in a cool, dark place in a container that does NOT have an airtight seal, such as an envelope (it’s also a good idea to label the container so you remember what plant it is next spring). Another option- leave the seeds on the plants and some perennials will re-seed themselves naturally.
- Start planning your spring bulb garden now. Spring-blooming bulbs are planted in the fall to provide the chilling time required for spring blooms. Remember to prepare the soil and plant bulbs at the appropriate depth listed on the package for the species.
- Start planning for design changes to your landscape for next year. Fall and winter are the best times to get your plans in order, and spring is the best time to install the changes- so get ready early for next spring, because it will be here before you know it!
- Take a break and toss the football around. Afterward, enjoy some warm apple cider with cinnamon. Finally, rake your leaves into a giant pile and take turns jumping into them with the neighbor kids!
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