If you’re working with pine needles and monkey grass, you might wonder what plants do not like pine needles and monkey grass. These common garden materials are fantastic for some uses, but they can actually cause problems for certain plants. Knowing which ones to avoid can save you a lot of trouble and help your garden thrive.
Pine needles, or pine straw, are acidic and create a dense mat as they break down. Monkey grass, or liriope, is a tough, spreading ground cover. Both have traits that make them incompatible with some of your other garden favorites. Let’s look at which plants to keep away from them.
What Plants Do Not Like Pine Needles And Monkey Grass
This list includes plants that struggle with the acidity, moisture retention, or physical barriers created by these materials. It’s best to plant these elsewhere in your yard.
Plants That Dislike Acidic Pine Needle Mulch
Fresh pine needles lower soil pH as they decompose. While this is great for acid-lovers, it’s bad for plants that need neutral or sweet (alkaline) soil.
- Lavender: This Mediterranean herb needs excellent drainage and alkaline soil. Pine needles add acidity and can hold to much moisture at its crown, leading to rot.
- Clematis: These vines prefer “cool roots and sunny tops.” A thick, acidic mat of pine needles can keep the root zone too wet and too sour for their liking.
- Lilac: For big, fragrant blooms, lilacs need a more alkaline soil. Mulching with pine needles can prevent them from flowering well.
- Vegetable Garden Beds: Most veggies—like tomatoes, peppers, broccoli, and lettuce—prefer a neutral pH. Using pine straw here can hinder nutrient uptake.
Plants Overwhelmed by Monkey Grass Spread
Monkey grass is a vigorous spreader, both by clumps and underground runners (rhizomes). It can easily invade and choke out less aggressive plants.
- Small Annuals & Perennials: Delicate plants like pansies, violas, or small primroses will get smothered by the thick foliage and roots of monkey grass.
- Ground Covers That Can’t Compete: Avoid planting slower, low-growing covers like thyme, sedum, or ajuga near monkey grass. The liriope will likely take over the area.
- Shallow-Rooted Shrubs: Monkey grass competes fiercely for water and nutrients. Planting it right up against shrubs like azaleas or hydrangeas can stress them.
Plants That Need Specific Drainage Conditions
Both materials can alter how water moves through the soil. Pine needles mat down, and monkey grass forms a dense root mat. This is problematic for plants prone to rot.
- Succulents (Sedum, Sempervivum): They need fast-draining soil. A layer of pine needles or competing monkey grass roots traps moisture, causing stem and root rot.
- Russian Sage: It thrives in hot, dry, poor soil. The moisture retention from these materials will make its roots soggy and unhappy.
- Bearded Iris: Their rhizomes need to bake in the sun and have excellent air circulation. Covering them or planting them in a crowded, damp area invites disease.
What to Use Around These Sensitive Plants Instead
You have better options for mulching and bordering these sensitive plants. Here’s a quick guide:
- For plants that hate acid: Use neutral mulch like shredded hardwood, compost, or leaf mold. For lavender and succulents, inorganic mulch like gravel or crushed stone is perfect.
- To border aggressive monkey grass: Install a deep, sturdy edging barrier (at least 6 inches deep) between it and other plantings. Regularly trim the edges to keep runners in check.
- For general moisture-sensitive plants: Ensure the planting bed itself has amended, well-draining soil. Use a loose mulch that doesn’t form a tight mat.
Testing Your Soil pH
If you’ve used pine needles for a while, test your soil. You can buy a simple test kit. If the pH is too low (acidic) for your plants, you can gently raise it by applying garden lime according to package directions. But it’s easier to just avoid using the pine needles there in the first place.
Better Companions for Pine Needles and Monkey Grass
So where should you use these materials? They are not bad, they just need the right partner.
- Great with Pine Needles: Acid-loving plants like blueberries, azaleas, rhododendrons, camellias, and holly. The mulch keeps their roots cool and moist while maintaining the low pH they crave.
- Great with Monkey Grass: Use it as a standalone ground cover in tough areas, under large trees where little else grows, or in solid beds where you want a uniform, low-maintenance look. It pairs fine with deep-rooted trees.
A Quick Note on Aged Pine Needles
It’s worth mentioning that very old, composted pine needles lose much of their acidity. If you have a pile that’s broken down into a dark, crumbly material, it’s more neutral and can be used more broadly as a soil amendment. But fresh or slightly aged pine straw is what you need to be cautious with.
FAQ: Common Questions Answered
Q: Can I use pine needles around roses?
A: It’s not ideal. Most roses prefer a slightly acidic to neutral pH (6.0-7.0). Fresh pine needles can make the soil to acidic, affecting bloom. Shredded hardwood or compost is a safer choice.
Q: Will monkey grass kill my trees?
A: Mature trees with deep roots generally coexist fine. However, avoid planting monkey grass right against the trunk of a young tree, as it can compete for water during establishment.
Q: Are there any flowers that like pine needles?
A: Yes! Acid-loving flowering plants include begonias, hydrangeas (for blue flowers), impatiens, and trillium. They appreciate the mulch.
Q: How do I remove monkey grass if it’s where I don’t want it?
A: It takes persistence. Dig out clumps, ensuring you get the roots. You may need to use a garden fork to lift mats. For small sprouts, a careful application of a grass-specific herbicide can help, but manual removal is best for garden beds.
Understanding what plants do not like pine needles and monkey grass helps you make smarter gardening choices. By matching the right plant to the right condition, you save yourself work and create a healthier, more beautiful garden. Always consider a plant’s needs for soil, water, and space before adding mulch or companion plantings nearby.