As the gardening season comes to an end, we’re faced with the task of clearing up before winter arrives. While the general rule for generations has been to tidy up your garden by removing dead plants, there’s a growing trend to leave plant material to break down naturally over the winter.
This practice, known as “leaving plants in situ” (situ from the Latin’ in place’), has gained popularity in recent years because of the environmental and soil health benefits.
Naturally, I’m more inclined to think it’s growing in popularity because it’s easier than yanking everything up, but what do I know? What I do know is you should give it a try this year. Like everything else gardening-related, there’s a right way and a wrong way, and there are some caveats to this practice, but the benefits are worth sticking around reading about.
Justified Lazy Gardening – the Benefits of Letting Plants Decompose Over Winter
Leaving your spent veggie plants to break down over winter provides numerous benefits not just for your garden but also for local wildlife. Who knew doing nothing could be so good for your garden?
1. Soil Enrichment and Organic Matter
One of the biggest advantages of leaving plants to decompose is the natural addition of organic matter to the soil. As the plants break down, they release vital nutrients that they’ve drawn from the ground throughout the season. Things like calcium, magnesium, and the holy trinity of plant-growing nutrients – nitrogen, phosphorus, and potassium- go back into the soil.
We spend so much time during the growing season feeding our plants these nutrients, yet we rarely think of allowing them to put those nutrients back.
Additionally, as the plants decompose, the organic matter improves the structure of the soil by increasing its ability to retain moisture and nutrients. These are all good things if you want next year’s vegetables to have a healthy root system, especially your root vegetables.
Finally, letting this season’s plants waste away over winter stimulates microbial activity in the soil. We’re big on improving the soil microbiome here at Rural Sprout, as it’s pivotal to good soil health, which in turn means healthy gardens.
Soil microorganisms, such as bacteria and fungi, are what break down plant material into humus, that gorgeous, dark, rich soil we all want in our gardens. Over time, these microorganisms create a balanced soil ecosystem, giving you healthier, more productive plants, something you can’t do if you remove them every fall.
2. Erosion Prevention and Soil Structure
In regions where winters mean rain, snow, and wind, leaving plant matter in the garden can help prevent soil erosion. The roots of these dead plants anchor the soil, preventing it from washing away during heavy fall and spring rains, windy winter storms and melting snow.
When you remove your plants at the end of the growing season, you expose soil to the elements, increasing the risk of erosion and compaction. Compacted soil can be a pain to work with in the spring, as it becomes waterlogged and slow to drain – not ideal for planting seeds and young seedlings. By leaving plants in place, you maintain a protective natural mulch that helps keep the soil loose and ready for planting.
3. Habitat for Beneficial Insects
Letting plants rot in place over the winter provides a safe habitat for beneficial insects. Many pollinators, such as bees, butterflies, and beetles, overwinter in plant stems, leaf litter, and soil. For example, native bees often use hollow plant stems as nesting sites, while other insects lay eggs on or near plant debris, giving their offspring a safe place to emerge in the spring.
In addition to pollinators, decomposing plant matter also provides food and shelter for predatory insects like ladybugs and ground beetles. These natural predators help control pest populations, such as aphids and caterpillars, reducing the need for chemical pesticides in the garden.
While they may not winter over there, your dead plants provide a place for birds and small mammals that may seek shelter in the garden. Seeing birds hop around in your garden looking for seeds on a frosty morning is a great way to start the day.
4. Winter Interest and Aesthetic Appeal
Brown plants are transformed with the liberal application of frost or snow. Leaving plants in the garden adds a unique visual appeal to your winter landscape. Frost-covered seed heads stems, and branches can create stunning scenes during cold mornings.
5. Save Time & Your Back
From a practical perspective, allowing plants to decompose over winter naturally can save you time and effort. Fall clean-up can be a bear, especially in large gardens. By leaving your vegetables in place, you significantly reduce the amount of work you have to do at the end of the year. In the spring, much of the plant material will be broken down, and what’s left is much easier to remove.
There’s a Trick to It!
While the idea of leaving your garden in situ over winter is relatively simple, there are a few guidelines to ensure that it truly is time and labor-saving and you aren’t inadvertently making more work for yourself.
Keep Only Healthy Plants
Don’t leave diseased plants in your garden. Things such as powdery mildew, blight, or fungal infections can harbor pathogens that survive the winter and infect new plants in the spring.
Trim but Don’t Uproot
Okay, I get it. The “messy” appearance of leaving your plants to decompose isn’t for everyone. If you prefer a tidier appearance but still want to enjoy the benefits, you can trim back plants before winter. Cut them back to about 6-12 inches above the crown.
For larger, more unruly plants, you can chop the stems into smaller pieces and spread them over the soil as mulch. This will speed up the decomposition process and provide additional protection against soil erosion. A great time to do this is after the first hard frost, as Mother Nature has already started breaking the plants down for you.
The Caveats
As I mentioned in the beginning, there are a few caveats to this method. While the practice has many benefits, there are potential drawbacks to consider. In some cases, removing dead plants at the end of the growing season may be a better choice.
Disease and Pest Management
The most significant concern when leaving plants in the garden is the potential for disease and pests to persist. Some pathogens can survive in dead plant material over winter and reemerge in the spring, as previously discussed. If you have any disease issues during the growing season, it’s best to remove and destroy the affected plant material rather than leave it to decompose.
While many beneficial insects overwinter in garden debris, that also means many pests may find refuge in dead plant material, too. If you had a severe infestation this season and the pest in question winters over, then cleaning up the garden can help disrupt the life cycles of these pests and reduce their populations next year.
Weed Management
This year’s favorite plant can easily turn into next year’s weeds if you aren’t careful. Leaving certain plants in the garden can lead to fruit rotting and populating the soil with seeds. Under the right circumstances, you may end up with volunteers of that plant for years to come. While it’s to your advantage to have some plants volunteer from year to year, some can spread and become a weed rather than a welcome addition. (I’m looking at you, ground cherry.)
In the end, letting your plants break down in your garden over winter offers you an easy solution to fall clean up along with added benefits to the soil. Let’s give it a try this year.
Get the famous Rural Sprout newsletter delivered to your inbox.
Including Sunday musings from our editor, Tracey, as well as “What’s Up Wednesday” our roundup of what’s in season and new article updates and alerts.