Fall Garden Practices

Plant as many native plants as you can fit into your space! Fall is a great time for planting.

Trees can be planted in the fall, early winter, spring, and summer (in mild areas). That said, fall is a great time because the soil is warm from the summer, but the air is cooling. This makes digging a hole and allowing the roots to settle into a warm environment, ideal. Fall, however, can also be a dry period in some areas, so if rain or precipitation is scarce, water your tree every few days for a week or two while it settles in. Native tree species will quickly adjust to the local conditions. Do make sure to dig an adequate hole for your tree or plant, as in frost-prone areas, plants which haven’t had time to establish their roots in their new home can get “heaved out” when the ground freezes.

Elderberry and most native shrubs do not need to be trimmed. If they are growing too rapidly or growing over other foliage, it is best to trim most native shrubs in the late winter before they begin to bud out and after the fruit has been consumed by birds or other wildlife. Note that when trimming flower-producing shrubs, you will likely trim off some of the flower buds making for less flowers and ultimately less foraging for pollinators. Thus, prune modestly and or do a pruning rotation where you prune one set of flowering shrubs one year and another the next to minimize a drastic drop in spring flowers for pollinators.

Many native plants can tolerate thick layers of leaf litter. This is what happens naturally in forests – in fact, introduced earthworms mean that leaves are broken down into the soil much faster than they would be naturally. In the north, snow, and elsewhere, rainfall, will flatten the pile down considerably. If you have very young, or recently planted plants, they may benefit from a gentle helping hand in the spring – you can gently part the leaves a little to help them reach the light. If you are growing desert plants, or plants from other naturally sparse ecosystems, use mulch sparingly if at all.

You can leave the leaves on plant beds all year round if you like – this is generally what happens in nature, and native plants have evolved to deal with it.

Any kind of mechanical disturbance risks injuring or killing the many larvae and pupae that need a safe place to overwinter; mechanical mulching can be particularly destructive. Gently raking leaves into areas where they can be left alone well into the following spring is the best approach for places where you can’t simply leave them where they fall.

Most leaf species, including non-native leaves such as Norway maple, are generally perfectly fine to use as mulch. They will not harm the soil or any native plants you are trying to grow. There are plenty of native plants which do just fine under walnut trees and leaf litter, but walnut mulch may not be the best choice for your vegetable garden as it may inhibit the growth of food plants. Do also be careful as leaf litter is likely to also include seeds, so applying e.g. Norway maple mulch will mean you’ll have to be vigilant for Norway maple seedlings establishing. These are fairly easy to pull up – especially from a thick layer of leaf litter. Be careful too if you are using material raked from gardens containing invasive plants such as periwinkle, Japanese spurge and similar, as fragments of these species can grow and establish in new areas.

If you think about a meadow or natural area, there isn’t much reason for any plants to have their flowers removed other than by a foraging or passing animal. Thus, the only real reason habitat gardeners would be dead-heading is if they don’t want that particular plant to spread its seeds. If you do need to dead-head we encourage you to sprinkle the seeds in an area where they still be available for foraging birds or an area where you are trying to grow more of the species you dead-headed.

Different species of bees and other insects have different needs when it comes to stems. In general, the more hollow the stem, the more beneficial to nesting bees. That said, there are a variety of different uses in stems, for instance the galls created by gall flies on goldenrod. This is one reason why planting a diversity of native flowering plants – and leaving the stems – maximizes the resources available to foraging or nesting insects.

Dried stalks should be left for at least an entire growing season after they flowered as bees generally use the previous years stalks for creating nesting cavities. Stalks can be cut to 1-2 feet. The new growth will grow up and cover the old stalks quickly in the spring. Letting stalks naturally fall off and decompose is recommended.

There isn’t an ideal time as different bees and caterpillars emerge at different times of the year. One rule of thumb is to delay your clean-up as long as possible in the spring when evening temperatures in your region are in the high 40s or low 50s (4 – 10 C) for consecutive nights. This provides time for some early pollinators to emerge from their wintering habitats before beginning clean-up. However, insects are running through their lifecycles all year round, so there is a risk you’ll be disturbing something at any point. Leave as much as you can for as long as possible for maximum biodiversity benefits. And, try to leave the stems and flowers in the garden, if possible, by using them as a border that the new growth will cover as it fills in.

The meadow or unmowed area should not be mowed until late spring. And, if possible, mow only a third of your meadow each spring, leaving two-thirds for all the biodiversity to thrive. Mowing will inevitably disturb pollinators and other organisms in your meadow, so leaving a portion of it it unmowed every year can help. If your meadow is supporting nesting birds, pay attention to the onset of breeding and avoid any disturbance between April/May and the end of July/August, give or take a few weeks at either end depending on your latitude.

Yes! If you do want to rake the leaves, do so, and put the piles in corners of the property where they can decompose and the leaf litter critters have a chance of emerging in the spring. Perhaps an area that is not well traveled or viewable from the road or walkways.

If you do cut seedheads, consider spreading the seeds in place or near areas where birds can forage safely in the winter. This will allow them an opportunity to still hunt for the seeds. Warning, native plants will spread in this new area so only do this for plants you want to encourage. Also leave the stems somewhere on the property in case there are nesting bees in the stalks.

Keeping distinct mowed edges around or outlining the native garden space is another way to signal that the plants that are being kept are intentionally left.

You can leave annuals in the gardens. They may also provide foraging resources for birds. If they are nonnative, however, they likely don’t provide a ton of ecological service, so they can be removed from the garden to make space for your native perennials to spread.

Yes, you can leave native plant leaves and stems and they won’t harm the native plant community. Unless you have a particularly large volume of a specific species which is particularly toxic, composting should be just fine.

The short answer is, yes! Fire and smoke most certainly affect birds and pollinators. There is still a lot we do not know about the impacts, but here is one article and another that may help. And, here is one about recovery as it relates to the Palisades fire in California.

In fire-prone areas, follow local guidelines concerning set-back distances of plants and organic material. There are various “fire smart” guidelines online with recommendations for vegetation management around structures. It is best not to stack flammable materials like leaves, stems and branches close to buildings. Don’t let leaves accumulate under decks or in windowwells. You may need to keep a plant-free zone around your house, using gravel or rock.

Spend time exploring your local ecosystems, getting to know the plants which are native there, and look at what happens to plant material naturally. Some sparse ecosystems do not accumulate much plant material – either living or dead – and that’s just fine!

Yes! You can leave your vegetables in place over the winter and wildlife will certainly enjoy foraging on the drying foliage or around the plants. Birds may harvest cabbage moths and other late-season caterpillars of the brassica family. Or, worms, ants, and other insects that are slowly burrowing down into the soil for the cooler months may be hunted by birds.

Keep in mind, however, that to minimize disease and pests, many vegetable gardeners and farmers remove debris from their beds to risk disease-spread or continued pest pressure in the following year. Use your judgement about how the plants did and if you noticed pest damage, or not, when deciding whether to leave vegetable gardens intact until spring planting.

This is a difficult question as the squash family has both a lot of pests that are attracted to them and the plants generally don’t decompose in a way that is visually appealing. Perhaps you could consider keeping the fruits (pumpkins) and cutting the tops off and leaving them out for birds and other wildlife to harvest the seeds? They most certainly will find them. 

Once the flesh of the pumpkin begins to decompose it can smell and mold, which may be unappealing both to the neighborhood and make it less likely to be visited by birds. This may be the time to compost what is left of the pumpkins. Note that because of squash bugs, cucumber beetles, etc., you’ll want to keep decomposing squash-family plants away from vegetable gardens as many of these creatures will overwinter in and around the soil and foliage of the squash plants.

In general, no, this is a sign of decomposition in progress and that mold will eventually allow the leaves to biodegrade and improve the quality of your soil. That said, mold can trigger reactions and health concerns in humans and pets in areas with poor air flow. If you notice a lot of mold and you or others in your family are sensitive, we recommend trying to keep your decomposing leaf pile as far away from where humans may come into contact with it. Generally the mold will give way to dark, nutrient rich soil. The pile can also be covered with a tarp or another barrier that minimizes the amount of spores that are released.

Decomposition of leaves leads to some mold development. If it is a concern, try leaving the leaves as far away as possible from where humans and pets may come into contact with it and cover it with a tarp or another barrier when it is actively biodegrading.

Small mammals are a part of our ecosystems. Creating an environment only for birds is near impossible. That said, there are things you can do to encourage more birds and less rodents. First and foremost, plant native flowers, shrubs, and trees to feed the birds rather than bird feeders. Bird feeders (even squirrel-proof options) will attract rodents to your yard. Native landscaping will still attract them, but in smaller numbers and spread out over the growing season.

If you do feed the birds, choose squirrel-proof feeders and clean up under your feeders regularly so they are not as attractive to small rodents. And, if your site is suitable, consider adding a nestbox for owls or American kestrels. These are our natural rodent management team!

Finally, if you want to see birds up close all year without feeders, a birdbath is almost as effective for attracting birds. Small mammals, though they can use it, are less likely to use a water source than they are bird feeders.

Part of gardening is embracing a dynamic, adventurous, unpredictable (sometimes), and learn-on-the-job experience. Mold, plant pests and diseases, squirrels, rodents, etc. are all part of many of our natural ecosystems, and can be perfectly benign. However, it is also important to consider your health and the sustainability of your home. Don’t let plant material accumulate against structures, as this can lead to rot and damage, and can increase fire risk in dry conditions. This can also provide attractive habitat for small mammals which may then find their way into your buildings. The more native plants you can plant, the more of an ecosystem you will be supporting, and this includes natural pest controllers – predators and other mechanisms which keep things in some sort of a balance.

Ticks can be present in leaf piles. There is conflicting research about the best strategy for how to manage leaves when it comes to residential landscapes. The piles provide moisture and overwintering areas for ticks. This is one case for leaving leaves in place (not creating thick piles) because the thicker the layer, the more moisture and potentially more ticks can be found. 

That said, it is not always possible to leave leaves based on rules and regulations in Home Owner Associations (HOAs), towns, neighborhoods, and municipalities. Removing leaves to a place where they can naturally decompose, but be less likely to impact humans is ideal. Once leaves are bagged and shipped off to landfills, the likelihood of the life in the leaf litter surviving is low. 

Managing our landscapes for wildlife is always a juggle between maximizing the benefits and minimizing things such as tick populations. Ticks are in our landscapes and the best prevention is protecting yourself from exposure by keeping well cleared walkways through your plantings, wearing tick-proof clothing, and conducting a thorough tick-check after your gardening work. Drying your gardening clothes for 15 minutes on high after you come in will kill any ticks that may be roaming your clothing.

In some areas, careful research has shown that disease-carrying ticks occur in higher numbers in areas dominated by some species of invasive plants (see for example this and this article). Climate change is indeed also highly likely to be a factor in the increase in prevalence of disease-carrying ticks. A restored system with native plants supporting a full suite of ecosystem processes is one of our best defences against ticks. That being said, keeping well cleared walkways through your plantings, wearing tick-proof clothing, and conducting a thorough tick-check after your gardening work is always prudent.

As with gardens themselves, having a neat and tidy “edge” can go a remarkably long way in making the area look more acceptable. Having structure (things like birdbaths, artistically-positioned rocks or sculptures, attractive logs), and walkways which are well defined can make a messy area look well managed and tidy. You can rake the leaves off the walkways and edges and pile them into the garden beds themselves. You may choose to do slightly more vigorous “tidy up” of highly visible areas, while leaving other areas less managed. Adding additional material should not be necessary.

Our gardens are a small but important piece of what we all need to do to arrest declines in biodiversity. The bigger the area, the more the impact – we do also need to protect and restore thousands of acres of land across the world to truly make a difference. However, on a local scale, even small handfuls of native plants here and there do make a difference, and cumulatively, these differences add up to a lot. Private gardens and lawns amount to a huge area of land which should be managed with biodiversity in mind, and yet many are managed in very damaging and unhelpful ways.

This is a difficult question to thoroughly answer as different cities and states have different principles when it comes to managing public spaces. This is one of the best examples of a community trying to make an impact at the municipal level that may be of interest.

Homegrown National Park is also trying to increase their resources to better guide people in how to make broader impacts in their community by talking to neighbors, working with HOAs and adjusting community landscaping practices.

Generally, sawflies overwinter in the soil. Leaf litter or no leaf litter will not impact whether there are sawflies present. Leaf litter may help insulate the soil for any soil-dwelling creatures. Other biological controls for sawflies may be warranted and these are generally applied to the soil in the late fall or early spring.

If the leaf disease is spread and transmitted through the leaves, this is one time where leaves can be removed from the site, with the awareness that overwintering insects will also be eliminated. Leaves are a natural soil fertilizer and if the leaves are not transmitting disease, leaving them will nourish the soil, feeding the plant for a better chance at warding off disease in future years..

Yes! This is a great way of leaving the leaves and drying plant material on site, but also making your life more manageable for cleaning up after your dog. The pile will slowly decompose and many of the critters burrowed in the pile will still emerge in the spring.

Monarchs can be hit or miss! You can add several different species of milkweed – check for which are native to your area, and add as many as possible. Make sure you also plant some native later-flowering species as well, as these late nectar resources are important for fueling their return migration south in the fall. Bear in mind that it can be quite difficult to spot eggs and even caterpillars, so if you have milkweeds, it’s quite possible you have had monarchs already. Butterfly bush (Buddleia) and rose of sharon are non-native and can be invasive, so see what else you can find which are native and give insects the nutrition they need.

Dried stalks should be left for at least an entire growing season after they flowered as bees generally use the previous years stalks for creating nesting cavities. Stalks can be cut to 1-2 feet. The new growth will grow up and cover the old stalks quickly in the spring. Letting stalks naturally fall off and decompose is recommended.

Some animals are “generalists”, able to eat from a variety of food sources. This is true for insects, birds, mammals etc. However, there are also many specialist animals, including insects, which have evolved to be able to make use of only one species or one species group of plants. As we homogenize our world with a small number of plants, we lose these specialist species and everything which in turn depends on them.

The Audubon Plant Finder tool is the best resource for matching birds and the native trees and shrubs that will feed them in your specific ecoregion. Search this database using your zip code for the most accurate results.

While we always recommend feeding birds with native plants, having bird feeders of any type may be a great addition to your habitat offerings. Make sure to clean feeders 1x a week with a mild soap. Hummingbird feeders may need to be cleaned more regularly and red food coloring should never be included with the sugar-water.