University of Vermont Extension 
Department of Plant and Soil Science

Fall News Article

 
LATE FALL IN THE PERENNIAL GARDEN

Dr. Leonard Perry, Extension Professor
University of Vermont
                       
If you're like me and haven't quite got your perennial garden in top shape, fall is a great time to catch up and have it ready for rapid spring growth.  Fall is more leisurely, it is more cooling working outside, weeds don't grow back, and you can go into winter feeling a sense of order and accomplishment.  Here are 10 activities I "try" to get to each fall.
           
1. Cutting back.  I used to leave perennials until spring so their leaves and stems would recycle nutrients back into the soil, as well as providing seeds for birds in fall.  There never seems enough time in spring, though, so I have begun cleaning up and cutting back in the fall.  I still leave ornamental grasses and plants with attractive seedheads.  This way I have some fall effect yet less cutting back in spring.
           
2. Checking labels. I like to keep track of what I planted, and over time labels seem to drift around, the writing wears off, or plastic labels break when exposed to sunlight.  As a famous garden writer once said, the only thing worse than a plant without a label is a label without a plant.  For large markers, what I've found work best are the soft aluminum labels you write on and make an impression. Even if the ink fades, the impression remains to identify the plant. Plastic labels, which require replacing yearly or as they become brittle in sunlight, work well. Best is to write on them with pencil (which often holds up better than "permanent" markers).
           
3. Planting spring bulbs.  Ideally spring-flowering bulbs should be planted in late-September through October in the north.  But if they aren't in the ground yet, better to plant late than wait or not plant at all. 
          
4. Caging tall plants.  If you have tall perennials, an effective method of staking is to make a cage of wide mesh fence to place around them. During the slower fall months when you're not busy mowing and weeding, make some of these up and place on taller plants once you cut them back. If in a windy area, you may also have to put in a stake with the cage to hold it in place. You may have a couple of different sizes for different height perennials. Plants will then grow up through the cage next spring, often hiding it entirely.
           
5. Soil testing and amending.  It is a good idea to test your soil every year or two, amending it with lime and nutrients as needed.  Kits are available from many garden stores and your local Extension office.  Lime is important to adjust the soil pH, raising it when too low or acid.  Without the proper soil pH nutrients wont be as available, and plants wont grow as well.  As lime is slow acting, fall is a great time to add it if needed, so it can improve the soil by spring.
           
6.  Adding compost.  A soil amendment you really can't have too much of is compost.  It adds some nutrients, improves soil structure, and helps soil microorganisms that help plants.  I like to add a shovel full or two around perennials once cut back in the fall so it too can act over winter, working into the soil. If buying compost, make sure it is from a reputable source and weed free. 
           
7. Rodent and animal prevention. Rodents such as voles or field mice are looking for winter homes this time of year and getting set up.  Cutting back perennials and disposing of the stems (such as composting), keeping grassy areas mowed, and traps are all effective deterrents. 

For voles, an effective trap is to bait an inexpensive spring trap with peanut butter, placing it by an entry hole to their burrow, and then placing a pot over the hole to trap. This way they think they're still in the burrow and come for the bait. 

If planting bulbs such as tulips that squirrels and chipmunks love to dig up, place wire mesh on top of the bed.  Avoid bonemeal (attracts skunks which dig but don't eat bulbs), using another source of phosphorus such as rock phosphate (organic) or superphosphate instead.  Covering the bed with sharp stones or shells helps prevent digging too.
          
8. Dividing peonies. Wait to spring to divide most perennials when they are beginning active growth, but divide peonies most any time in the fall.  Keep in mind they may not bloom the following spring while they are getting new roots and growth.
           
9. Edging beds. Having a neatly edged bed does more than just keep surrounding grass from growing into it.  A neat edge provides a sense of satisfaction, beauty, and for a "wild" bed that is natural or just out of control, indicates there is a bed there and a purpose.
           
10.  Storing tools and chemicals.  Use a brush and water to scrub your tools, then wipe with a light coating or spray of oil (such as cooking oil).  Many use a 5-gallon bucket filled with sand and a quart of motor oil.  After using tools, scrape and rinse the heaviest dirt off, then push the tools in and out of the sand mixture a few times.  The sand helps remove other dirt, the oil helps prevent rust.
           
Don't forget to sharpen hoes and cutting tools such as pruners.  Sharpening stones or power grinders and sharpeners are available at complete garden and hardware stores.
           
Don't forget to disconnect and drain garden hoses on a warm day before they freeze solid for winter.  The same applies to sprayers. Otherwise you may have openings in the spring not just at the ends!  If you have chemicals, especially liquids, in an outdoor shed or unheated area, make sure they get stored in a non-freezing place over winter.
           

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