Don’t be fooled by the term green mulch. It’s not a weird new trend to camouflage woodchips with green food dye. Green mulch is also known as living mulch and essentially uses living plants that are densely sown and serve as mulch. They provide soil fertility, prevent runoff, and suppress weeds while looking beautiful. This landscaping method is a favorite of folks who don’t love the look of wooden mulch and rocks, favoring a cohesive and intentional layout. Creeping green mulches are called garden weavers. How cute is that?
While traditional mulching benefits fade and growers must replenish them for aesthetic purposes. It can also be expensive and labor-intensive to mulch in and around your garden annually. Additionally, hardwood chips may pull nitrogen from your garden, leaving less for your crops to glean. Green mulching is an eco-friendly practice that supports local wildlife, pollinators, and birds. It’s excellent in conjunction with native plantings and perennial gardens.
If you want to trade in annual woodchip mulching for something more agreeable to your lifestyle and garden design, keep reading for 13 great plants you can use as green mulch.
‘Tiny Tim Sweet Alyssum’
Tiny Tim Sweet Alyssum Seeds
‘Blue Grama Grass’
‘Red Giant’ Mustard
Common Blue Violet
Variegated fritillary butterflies rely solely on violets for egg-laying.
Blooming a light blue violet in the spring and summer, this stemless, fast-spreading violet is a perennial wildflower that remains low to the ground. It’s easy to dig up, split, and transplant where you’d like more to grow.
This species is very adaptable, growing in virtually uninhabitable soils just fine. Some gardeners refer to common violets as a weed, but I encourage you to embrace their ability to outcompete invasive plants like mock strawberries.
According to the Xerces Society for Invertebrate Conservation, violets are an important food source for variegated fritillary butterflies as one of the only host plants they’ll lay their eggs on!
Moss or Creeping Phlox
Use this plant in xeriscapes or rock gardens.
An incredible weed suppressant, creeping phlox spreads quickly but is gentle and comes in gorgeous brights or romantic pastels. The flowering moss forms a soft mat and will curve softly around other garden plants. The greenery remains attractive after the flowers fade in late summer.
Space plants at 1 to 1 ½ feet at transplant. Water them in, but allow them to almost dry out in between sessions. They prefer well-draining, slightly dry conditions and will even perform well in rocky or sandy areas.
Try ‘Emerald Blue’ for a soft lilac or ‘Emerald Pink’ for a bright pink. Colors will be the most vibrant when grown in full sun, but plants can tolerate partial shade. Use creeping phlox along xeriscapes or in rock gardens.
Sweet Alyssum
This tender perennial self-seeds, returning next season.
This tiny white flower is a vegetable gardener’s best friend. It will form a gentle, white carpet around your annuals, keeping weed pressure down and lending a hand to the local ecosystem.
Sweet Alyssum, or Alyssum, attracts beneficial insects like lacewings, syrphid flies, and parasitic wasps. The flowers exude a lovely sweet floral scent.
This tender perennial can be left in place. The plants will self-seed and appear next season. If you grow colored cultivars such as ‘Oriental Nights’ or ‘Rosie O’Day’, they may revert to white in subsequent seasons.
Phacelia
Flowers rich in nectar support local pollinators and insects.
Phacelia is a gorgeous fluffy, light purple flower grown as an annual or cover crop. Seeds germinate best in cooler temperatures and can adapt to poor soil conditions. Flowers will appear six to eight weeks after sowing. They can be used as casual cut flowers.
For mass seeding, spread about three ounces over 1000 square feet, scratch it into the surface, and cover it with straw or mulched leaves. Its flowers are rich in nectar and support many local pollinators and beneficial insects. Easy to add to a naturalized area or xeriscapes.
Don’t worry about watering much. They’ll adapt to low water levels. Northern growers can leave the residue in place, and it will serve as winter mulch after it’s killed at around 18°F (-8°C).
Buckwheat
This plant attracts pollinators and emits a sweet fragrance.
Buckwheat is an awesome, fast-maturing, and highly beneficial summer cover crop that can be used across many zones. Gardeners love it for its ability to germinate, pollinate, and mature in just 10 to 12 weeks, when it can be terminated. It’s especially useful when seasons are short.
After termination, it can be tarped to speed up the breakdown or debris can be left in place. Plant directly into the debris to serve as mulch that will continue to break down and add fertility, help maintain moisture, and suppress weeds. It’s believed to make phosphorus more available for future plants, but its benefits need more research.
Buckwheat is broadcast-established and can be sown alone as a quick cover crop before summer annuals or added to cover crop cocktail mixes. A full stand will be buzzing with pollinators at its peak flowering stage and it emits a sweet fragrance. For a bit more color, try ruby buckwheat. Beneficial and beautiful!
Blue Grama Grass
Ensure this grass has access to full sun for optimal growth.
This fancy perennial grass resembles cartoon eyelashes blowing in the wind. It’s one of the most heat and drought-tolerant native grass types, and it’s easy to blend into your lawn. Alternatively, place it along a driveway, roadside, or blank space in rock gardens. Blue grama is highly adaptable to poor conditions, including heavy clays.
Blue grama is a grazing option for native wild animals and birds and is great for erosion control. It’s also a host plant for skipper butterflies and provides food for many butterfly variety larvae.
This grass spreads slowly by rhizomes and requires little maintenance. Ensure access to full sun, well-draining, and balanced soil.
Crimson Clover
Use organic fertilizer or compost for best results.
Crimson clover, a part of the legume family, is a rockstar at fixing nitrogen and suppressing weeds competing with plants growing nearby. It features dense foliage and an attractive, fluffy red flower adored by pollinators.
The soil must be well-draining with good access to sun. Mix in organic fertilizer or top the area with compost to yield the best results. When crimson clover reaches the late bloom state before it’s turned in, it can add up to 150 lbs of nitrogen per acre.
Allow the debris to break down for at least three weeks before planting another crop. This will allow soil microbials to stabilize. After working hard for you all summer, it makes an excellent winter-kill manure for northern region growers where it may not survive. Note that this plant is an invasive species in some areas. Check with your local extension office if you’re unsure that the state you live in is one of them.
Comfrey
This hardy perennial attracts bees with its sweet nectar.
You may be familiar with comfrey as a powerful leaf, root, powder, and herbal powder widely used in health and skin care. But did you know it’s also an incredible amendment in the garden?
This hardy and cold-tolerant perennial establishes deep, strong roots, goes dormant in the winter, and emerges again each spring. When in bloom, their sweet nectar will attract bees. However, this is another invasive plant, especially in some eastern regions of North America. Opt for something else if you live in one of these areas.
Common Purslane
Weeds left to decompose enrich soil naturally.
Purslane, or moss rose, is a fast-growing juicy succulent that many gardeners will easily recognize and have experienced it as a fierce weed, often competing with annual vegetables and thriving in many conditions.
However, if you can stand to leave it in, it will protect the soil beneath crops like broccoli, summer squash, and kale by retaining moisture and suppressing weeds. The deep taproot draws moisture up to the surface, which nearby plants can benefit from. It’s also a powerhouse of vitamins, omega-3 fatty acids, antioxidants, and oxalates, and has a slight lemony flavor. Toss in a salad for a spin on traditional leafy greens alone, or pulse it into a unique pesto.
Note: Make sure to verify correct identification of purslane before consuming, and make sure you never eat any plants that have been exposed to herbicides or pesticides.
Sweet Woodruff
Plant this Sweet woodruff with spring bulbs and hostas.
Attention shade gardeners! This little starburst beauty thrives in shade and is as sweet as its name suggests. Dried leaves can be made into a tea, potpourri, and mosquito deterrent. Sweet woodruff will form a lovely green carpet, serving as a beneficial ground cover for shady areas on forest borders, rock, or woodland gardens.
Its shallow roots won’t get in the way of deeper root systems and plants are easy to maintain. Sweet woodruff isn’t considered invasive, but it won’t place nice with every species so experiment where you plant it. If you need to relocate it, dig out all the rhizomes or it will return to that area.
Sweet woodruff pairs well with spring bulbs and crocuses and alongside hostas.
Common Vetch
This plant enriches soil and controls erosion.
Common vetch is easy to establish in the spring and will produce abundant, dense growth, making it a great source of summer biomass and fixing nitrogen in the soil. Its multi-branched root system helps improve soil structure.
This annual poses less of a risk of becoming weedy, like hairy vetch. However, it is invasive in parts of the United States. Native birds, hummingbirds, and bees love vetch. It assists with enriching the soil and controlling erosion on hillsides and slopes. If it gets out of hand, it’s fairly easy to pull.
Common vetch seeds are inexpensive, the flower is gorgeous, and it is a powerhouse in the garden. Ensure the soil is well-balanced and well-draining, but it can withstand and help improve heavy soils.
Mustard
Timely termination prevents seed drop issues next season.
Mustard is an incredible biofumigant due to its high levels of glucosinolates. When grown to maturity and tilled in, they are released into the soil, decreasing the need for as many pesticides. It’s a powerful soil-borne pest management tool that has a cleansing effect and immobilizes heavy metals.
In a no-till system, small garden, or homestead, mustard can be grown between annuals and cut down and used as green mulch. As the plant decomposes, similar benefits will be reaped. But make sure you aren’t planting this plant where it’s classed as an invasive species.
Mustard also looks beautiful when grown in mass, attracts beneficial insects, and suppresses weeds. Its deep taproots can extend several feet in search of water, thriving even in drought conditions. The termination timing must be prompt to avoid it dropping seeds, causing issues the following season.
Alfalfa
Proper timing is crucial to establish a stand before winter.
This perennial legume is used globally as a forage crop. It’s easy to grow and allows ranchers to grow livestock feed. Its long taproots help break up compaction and aerate the soil when grown as a cover crop.
When grown as green manure, alfalfa provides the garden with dense nitrogen, improves the soil structure, suppresses weeds, and attracts beneficial insects.
Till alfalfa debris into the soil to add organic matter and fertility or cut it down and use as green mulch. Beware, alfalfa will drop seeds if you let it, and the timing must be right when trying to establish a stand before winter.
Final Thoughts
To move from annual mulching with external inputs like woodchips or straw, practice green mulching with live plants instead. It adds a new look to your garden and has many soil benefits. Plus, your local pollinators and wildlife will love it. Avoid anything that may become invasive in your region, and don’t be afraid to add color.
