Can You Compost Pine Needles? (If Yes, Then How?)

There is a common misconception that pine needles acidify the soil. But did you know they’re also a good carbon source and help structure your soil? Well, they are, and that’s why they are also commonly used as organic mulch. But can you compost pine needles? If so, then how?

Yes, pine needles are compostable, and when used correctly, they condition the soil by adding nutrient-rich humus. However, they must be used in moderation. Furthermore, shred the pine needles into smaller pieces to speed up the decomposition process.

How to Compost Pine Needles?

Pine needles are a great source of organic material. They are considered brown feedstock and add structure to your compost pile. As the pine needles take time to break down, hot composting is the ideal method to compost them.

Hot composting is an aerobic composting method that needs the vigorous action of microbes to break down the composting materials into humus. For hot composting, you need to balance nitrogen (green materials), carbon (brown materials), oxygen (air), and moisture (water).

Pine Needles

Follow this step-by-step guide to compost pine needles effectively through hot composting.

Step 1. Set Up Your Compost Pile/ Bin

To make the compost, you first need a compost bin. You can use an old plastic bucket or container at your home by drilling holes across them. Place the bin where you get sunlight. You can also choose a sunny spot in your garden and pile the materials over there.

Step 2. Shred the Pine Needles

To hasten the decomposition process, you need to chop the pine needles into small pieces. This increases the surface area of the needles in the compost pile and makes it easy for the microbes to act upon.

Step 3. Add Pine Needles

At the bottom of the compost bin, start adding pine needles and make a nice layer. After that, water the layer until it’s adequately wet.

You can also mix other brown materials like dry leaves and other yard waste with pine needles. Generally, dry oak leaves are mixed with pine straw for composting.

Step 4. Add Green Materials

Now, add a layer of Nitrogen-rich materials like grass clippings, fruits, and vegetable waste, coffee grounds, eggshells, and other kitchen waste.

Step 5. Repeat the Layers

Alter the brown and green layers until you have finished all the composting materials, and then seal the pile with a thick layer of pine needles at the top. Finally, water the compost pile.

Maintaining the Carbon to Nitrogen ratio is crucial for effective hot composting. Ideally, the compost pile should be 25 parts carbon to one part nitrogen.

Step 6. Maintain Your Compost Pile

Check the moisture levels regularly and water the compost pile with a hosepipe to carry out microbial action. You also need to mix the materials and turn them in twice a week. This ensures aeration and keeps the temperature high in your compost pile.

Your finished compost will be prepared to use for your vegetable garden or flower bed within two months. When the compost is ready, it will turn brownish in color with an earthy smell.

Can Pine Needles be Composted via Vermicomposting?

It is not recommended to compost pine needles through vermicomposting for several reasons. Firstly, Conifers contain high concentrations of terpenes and hexane that are toxic, and worms are sensitive to these hydrocarbons.

Furthermore, the waxy cuticle and dry cellulose of the pine needles make them difficult for worms to chew. Lastly, the acidic nature of the pine needle keeps the worms away, and they feel desiccated.

However, if these needles are pre-digested in the compost bin, they can then be added to your worm bins.

Potato Peels In a Worm Bin

Do Pine Needles Really Make the Compost Acidic?

There is a notion that pine needles are acidic and are not ideal for composting. Although the pH of fresh pine needles is indeed between 3.2 and 3.8, they lose their acidity once they fall down and start decomposing.

So, the best practice is to leave the pine needles as the natural mulch once they fall off the pine tree and later add them to compost. This will reduce the pH of the needles and make them neutral.

Furthermore, even if you add fresh needles to the compost bin, the microbial action will turn the finished compost neutral. However, it reduces the decomposition rate as the pine needles’ acidic nature may have some adverse effects on fungi and bacteria in the compost.

In a nutshell, the acidity of the pine needles remains on the soil surface and does not have a major impact. So it is safe to compost pine needles without worrying that they will alter the soil pH and make it acidic.

How to Compost Pine Needles Faster?

Pine needles take their sweet time decomposing due to the wax coating and low pH. Here are a few methods that will help you cut down the decomposition time.

Compost Pine Needles Faster

1. Use Pre-Digested Pine Needles: Use the pine needles as an organic mulch for one season and let them decompose naturally. You can also leave the pine straw under the tree to act as protection for the pine trees.

Another option is to collect all of the fallen pine needles and pile them together to allow them to decompose naturally through the action of the sun and rain. As the needles start to decompose, the wax cuticle will break naturally, and they are good to go to your compost bin.

The pre-digested pine needles decompose quickly in about six weeks when added to the compost bin.

2. Shred the Pine Needles Before Composting: Like other composting materials, pine needles also break down quickly when added as small pieces. Chop them into smaller pieces using a garden shredder or wood chipper before adding them to the compost bin.

You can also make a heap of pine needles and run a lawnmower to shred them finely. The smaller the pieces, the faster they will decompose.

3. Soak Them in Water: Break the pine needles into pieces and soak them for 24-48 hours. Generally, the waxy cuticle in the needles does not absorb the water and delays the decomposition. When soaked in water, the dampness of the needles attracts microbes to act upon them, increasing the breakdown speed.

Benefits of Composting Pine Needles

While many people mistake pine needles as harmful to soil and plants, they actually come with several benefits. Here are a few benefits you need to consider for composting them:

  • Pine needles do not compact and promote aeration in your compost bin.
  • Pine needles add carbon and structure to your compost.
  • They help with moisture retention in the compost pile.
  • Pine needle compost helps plants tolerate drought and other adverse conditions.
  • They provide organic material to the soil and help in plant growth.
  • It is economical and saves you from buying costly fertilizers.

Additional Tips for Composting Pine Needles

Pine needles are a great supplement to the soil, but while composting them, you need to be careful as they are acidic in nature and slow to decompose. So here are a few tips for you to compost pine needles effortlessly:

  • Pine needles break down slowly, so limit their use in your compost pile. The recommended portion of pine needles in the compost is up to 10%.
  • Shred the pine needles into smaller pieces with a lawnmower. 
  • Using dry pine needles that are already used as organic mulch is best for composting as they break down quickly.
  • Soak pine needles in water for 24 hours for quick results.
  • Pine needles should be mixed with other composting materials( greens and browns).
  • If you consider composting large quantities of pine needles, compost them separately.
  • Avoid using needles from the roadside as they might contain heavy metals. Also, do not use the needles having dog droppings.

Mulching with Pine Needles

The pine needles interlock and stay intact, making it a good mulch option for acid-loving plants like rhododendrons, blueberries, raspberries, strawberries, and some vegetable crops like carrot, cucumber, sweet peppers, pumpkin, and tomato plants.

To make the pine mulch, spread a 4 -inch layer of pine straw around the trees and shrubs. Shake and toss the needles as you spread them to make the straw fluffy.

Mulching with Pine Needles

Here are some of the benefits of using pine needles as mulch:

  • Pine needles are light in weight, reduce manual labor to mulch your garden, and are considered better than heavy wood mulch or bark mulch.
  • They inhibit weed growth by blocking the sunlight from reaching the ground. 
  • Pine straw mulch decomposes slowly, and you need not replace the mulch regularly, saving your time and energy. Once they decompose, they enrich the soil. 
  • They insulate the soil by protecting the soil from high temperatures in summers and preventing freezing in winter.
  • Pine needles prevent erosion from the heavy rainfalls, and once they settle on the ground, they do not blow out with wind easily.

Frequently Asked Questions

How long does it take for pine needles to decompose naturally?

Pine needles break down slowly, taking up to 1-2 years to decompose completely if left on the ground. But once you compost them through hot composting, they can break down in up to two months. During the first few weeks, greens will break down, keeping the pine straw intact. So it is recommended to add the green materials once in a while.

Is pine mulch good for a vegetable garden?

Pine mulch is a great addition to your vegetable garden as they help in water retention and control the weeds. Moreover, it increases soil acidity while breaking down, and most vegetable plants grow well in acidic soil.

Should pine needles be left on the ground?

Leaving the fallen pine needles under the pine tree is an excellent idea as it serves as a mulch and nourishes the tree. When the pine needles start to break down, they shed their waxy coating, and when these dry pine needles are added to your compost bin, they decompose quickly.

What to do with dead pine needles?

You can use the pine needles as an organic mulch, a fire starter, a room freshener, or a disinfectant. In addition, you can brew a refreshing pine tea or have a warm footbath with these needles. They also have medicinal properties and control cough and congestion.

Are pine needles good for the garden?

Pine needles are organic waste and add nutrients to your plants through mulch and compost once they decompose. In addition, they help in aeration and increase soil porosity. So pine straw is a great option to supplement your garden.

Can you compost fresh pine needles?

It is recommended to leave the fresh pine needles on the ground or use them as a mulch for acid-loving plants. This makes the fresh needles lose their acidity and break the wax coating. If the fresh pine needles are used in compost, they may reduce the pH of the compost initially and delay the decomposition process.

Can you use pine cones in compost?

Yes, pine cones can be added to your compost but make sure to break them into smaller pieces before adding your pine cones to the compost. This makes them easy to break down.

Why do pine needles decompose slowly?

Pine needles have a waxy coating or cuticle, which repels water and slows down the decomposition. Also, the low pH of pine needles inhibits the action of microbes and delays the decomposition process.

If you have a pine tree in your backyard, you now know how to use the needles falling from it. Pine needles are an excellent addition to your garden and compost if used with care. So stop worrying about how to discard this organic waste and try to make the best out of them.

And similarly, if you want to learn more about composting dead or fresh flowers, check out our guide on composting flowers.