Cleaning up the garden in fall is a tradition as we get ready for winter. Rake the leaves, cut back perennials, cut the grass short – there is lots to do in the fall. The reality is that most of the fall cleanup jobs are not good for the environment. People clean up their gardens in fall for aesthetic reasons, not because it is good for the plants or the garden.
It’s time to rethink the whole process of fall cleanup.
Fall Cleanup in the Garden– Don’t Do It!
Many times in the garden we have a choice between doing what is good for the garden and aesthetics. We garden to have a nice place around our homes and therefore aesthetics is important. More and more people garden for the health of the environment and that is also important. Unfortunately many times these two goals conflict with one another.
Consider this simple example. Do you cut down a perennial in fall?
For aesthetic reasons the garden looks much neater if old dried flower stems are removed, but if you remove them, birds have less to eat and insects lose their winter homes.
Historically, a lot of garden advice was given for aesthetic reasons. Looks trumped the environment. In this blog I will make the environment more important than looks. It is time that we do things which are best for the other life forms around us.
Removing Perennial Leaves and Stems
What happens in nature? The leaves of perennials slowly dry and drop to the ground. Many will remain in place over the winter because it is too cold for them to decompose.
These leaves help to protect plant roots from the cold. They mulch the ground. Snow will collect on the leaves around the plant. Go outside in winter when we have only a bit of snow on the ground. Provided that you did not clean up the garden in fall you will see small piles of snow around each plant. This snow is a great warm blanket and further helps protect the plants.
Birds feed on the standing seed heads. This is an important food source for them to get ready for winter. It is best to leave seed heads alone in fall. The exception to this rule are seeds that spread too aggressively in your garden and become weeds.
The organic matter lying on the ground provides important protection for insects. Some of you are probably concerned about overwintering insect pests, but remember that nine out of ten insects are the good guys and if you give them a warm place to sleep over winter they will be there to protect your plants from pests next spring and summer.
Some people like to remove the leaves of perennials because in spring they are mushy and who wants to remove mush in spring? That is true, except that you don’t need to remove them in spring either. I just leave them in spring. In no time at all the new leaves cover the old ones and you don’t see them. By mid summer the old ones have decomposed.
Save the Bees
Many of our native bees spend the winter in tunnels in the ground, cracks in mortar, holes in dead wood or within hollow stems. They need the litter in the garden to survive.
What About Diseased Plant Material?
There is lots of talk about removing diseased plant material from the garden. The advice is that you should not compost it. Put it in bags and have it picked up as garbage.
This seems to make sense. Fungal and bacterial diseases produce spores which are dust like particles that will produce future disease problems. Why not get them off your property?
This is a case of something that makes common sense, but does not work in practice. Most spores are ubiquitous – they are everywhere. By the time your leaves are infected the soil is already covered in spores. No matter how hard you try you will not remove them all.
The second issue is that virtually all your plant material is infected by fall. Even if you can’t see the infection, it is on the leaves. If you follow the above advice you would need to collect every piece of organic matter and remove it from your property. Oh, and every one of your neighbors would also need to do the same thing.
Late blight of tomatoes is a fungus disease that travels 50 miles. How effective is your cleanup if your neighbors don’t? Very little.
You might as well compost it all. If you have plants that get diseased every year consider replacing them with things that don’t get as much disease. I don’t grow Monarda (bee balm) any more because it always has mildew in my garden. Problem solved.
Falling Tree Leaves
Tree leaves that fall onto flower beds should just be left there. The pile can be several feet thick. For most plants they provide excellent protection from the cold. In some cases the plant can’t take the extra wetness, but that is a rare case.
In spring, I do remove leaves if the pile is more than a few inches thick, so that the perennials can get light more easily. The removed leaves can then go into the compost pile.
Larger leaves, like maple and oak, that fall onto the lawn cannot be left there because they will kill the grass. You can run over them several times with a lawn mower and once the leaves are chopped up nice and fine they can be left on the lawn. They will break down next summer and feed the grass. But how environmentally friendly is this?
Instead of mowing, you can rake the leaves and add them to the compost pile. If some flower beds don’t have enough leaves, put them there. If you really have no way to use them, please give the leaves to a neighbor who composts. Do you have any idea how happy a gardener gets when they receive bags of leaves? It saves us the trouble of sneaking around the neighborhood at night, stealing them from your curb.
What About Walnut Leaves?
You have probably heard that leaves from walnut trees and all parts of the tree are allelopathic – they kill other plants or at least keep them from growing.
The truth of the matter is that most plants are not affected by walnuts. Some are, but usually only in the seedling stage. Almost all of the science around this topic was done in labs using seedlings. Besides, the culprit chemical Juglone, will decompose along with the leaves.
Planting Bulbs
If you still have some spring bulbs sitting around, plant them as soon as possible. I know that the common advice is to wait until the ground freezes, but that is just a garden myth that won’t go away.
Think about the spring bulbs you planted in previous years. They spend all summer and all fall in the ground. Why would newly purchased bulbs be any different? They aren’t. Bulbs do well in the ground where they don’t dry out so much. They also start to grow earlier than you think. In zone 5 garden they start making roots in September. Why would you wait until November to plant them?
Plant bulbs as soon as you get them.
Protect Trees from Rabbits
Fall is a good time to add extra protection for trees and shrubs so that various rodents don’t eat their bark in winter.
Wrap trees with a plastic tree wrap or chicken wire. This will keep animals from chewing on the bark in winter.
How high should the protection go? A rabbit can easily reach up 1-2 feet. Which means that if they are standing on 3 feet of show they can reach up to 5 feet.
Water the Woodies
Woodies is a term used for any tree or shrub – a plant that creates hard wood. Woodies are different from perennials in that they have parts of the plant above ground all winter. This means that they loose some moisture all winter long. Perennials on the other hand keep all of their plant parts under ground during winter and therefore loose very little water.
Water trees and shrubs right up to the time the ground is frozen. You may want the gardening season to be over but the trees and shrubs still need water. This is especially important for woodies that were planted in the last year. Their root system is still not fully grown and they need a good supply of water.
Mulching
There is a common belief that you should not mulch until the ground is frozen. The reason for this idea is that small rodents like mice and voles will make nests in the mulch if it is laid down too soon. If you wait until the ground is frozen they have already made their winter home somewhere else and not in your garden bed.
There is no evidence that any of this is true if you use wood chips or compost for the mulch. It might be true for things like straw.
If you are using wood chips for mulch, the best time to mulch is when you get the stuff. It should really be on your bed all year long.
The Last Cut for the Lawn
Traditional advice was that you should cut your grass short for the winter. This apparently reduces snow mold in the grass.
It turns out that is a myth. The last cut for the year should be at the same height as the rest of the year – the highest setting on your mower. Longer grass is healthier grass both in summer and in winter.
Here is a list of other fall jobs
- Collect seed
- Collect herbs for drying
- Empty water features
- Bring in tender plants and house plants
- Clean and sharpen garden tools
- Keep weeding
- Dig up tender bulbs and tubers
- Fertilize
- Clean gutters and evestroughs
- Empty hoses and irrigation systems
Support the environment and stop doing fall cleanup. If you are interested in reading about more garden myths hop over to http://www.gardenmyths.com, my other gardening blog.
References:
- Photo Source for Ladybugs hibernating; littlestschnauze
Can you comment on another ‘almanac myth’ that is perpetuated about totally cleaning up the vegetable garden (as opposed to a perennial garden) and that the “dead debris invites disease and insects.” One would think we want lots of debris from any garden for insects that provide additional food for overwintering birds as they shuffle among the debris looking for these insects. Would you not agree?
Thanks.
I always enjoy your posts. You never run out of myth busting topics.
Dead debris could and probably does harbor disease. Insect pests are less of a concern.
One thing to understand is that most of these diseases arrive in your garden from the air. So unless everyone cleans their garden you will have the disease spores again next year, even if you clean up your garden.
The trick is to understand the serious diseases you have, and ignore the minor ones. For example, tomatoes get septoria fungus easily but it rarely kills the plant or reduces harvest in my climate. I have always had it, with or without cleaning up, so I don’t worry about it. Late blight is deadly for tomatoes, but it will overwinter in our soil due to the cold winter. So cleaning up or not has no effect.
As a general rule, I don’t clean up. But if I got something where cleaning up would help, I might do it.
I am wondering when I can remove the leaves from the flower beds? It is late March and I am in Ontario, Canada. I believe Zone 6.
I usually remove them as they defrost.
Thanks for letting me know I can be lazy in the garden in the fall. I am worn out from this summer of no rain, hand watering 3 hrs every night was exhausting. Lucky for us it is raining weekly now. I’m still out there puttering, digging up summer bulbs and plants, planting fall bulbs and moving a few perennials. Could you tell me what you think about putting manure on the gardens in the fall, I used to do it in the spring but I’ve had a landscape person tell me to do it in the fall. Thanks again.
It may depend on how aged it is and how cold your climate is. Fresh manure should sit a while and winter is a good time for this, so fall is OK. If it is aged manure, people like to add it in spring because it will lose nitrogen over the winter when plants can’t use it – a waist of nitrogen. In colder climates it probably does not make much difference since it just sits there frozen.