Ornamental artillery plant, Pilea microphylla, aka gunpowder or pistol plant, military fern, or rockweed, is an herbaceous perennial.
It is one of about 600 types of non-stinging Pilea species in the Urticaceae, or nettle family.
This tropical species thrives outdoors year-round in Zones 11 to 12 as a short-lived evergreen perennial. It is also grown as an outdoor annual or indoor houseplant in all zones.
We link to vendors to help you find relevant products. If you buy from one of our links, we may earn a commission.
In this article, we’ll discuss all you need to know to grow and care for your own artillery plant indoors.
It has a creeping growth habit and may reach mature dimensions of six to 18 inches high and 12 to 24 inches wide.
The artillery species has plump leaves like a succulent. They are either green or variegated pink and white, one-eighth to one-half inch long, and “obovate,” or rounded and narrower at the base. The leaves are arranged in opposing pairs, like a fern frond.
In nature, the species produces tiny pinkish flowers followed by brown fruits. And while flowering is unlikely to occur indoors, it’s fun to know about it because the names “artillery,” “gunpowder,” “military,” and “pistol” come from an unusual characteristic.
There are both male and female flowers, and the males literally propel pollen into the air, as in an aerial attack.
Historically speaking, the artillery species has undergone numerous botanical reclassifications by Swedish botanist Carl Linnaeus and later botanists, including Parietaria microphylla (1759), Pilea muscosa (1821), P. microphylla (1851), and P. trianthemoides var. microphylla (1869).
These synonyms and “basionyms,” or name equivalents and their predecessors, still pop up in plant searches, so it’s good to be familiar with them.
The artillery species is native to the Caribbean, Mexico, Central and South America, and the southeastern United States.
In its native habitat, it is a somewhat weedy, spreading ground cover that commonly sprouts between rocks and in lawns, in margins between land and water, and in masonry crevices.
The species has been introduced around the world, and is classified as invasive or at high risk for becoming invasive in many places because it readily naturalizes via stolons, or runner roots, as well as self-sown seed.
Today’s cultivated varieties are robust versions of the hardscrabble wild species. And while indoor cultivation does not pose a threat to the landscape, we do not recommend letting P. microphylla spend the summer outdoors in temperate zones as we do with many houseplants, in order to avoid inadvertently introducing it to the landscape.
This tropical species thrives best with a daytime temperature range of 65 to 85°F and 1000 to 2000 foot-candles of daylight, which is another way of saying bright indirect light.
Lower light is well-tolerated but usually causes shading to dark green, so don’t waste money on a variegated variety if you choose a dim location for your plant.
And growth may be more horizontal than upright. A little pruning of leggy stems contributes to a more compact form.
If you have a very dim setting, such as a windowless office, that you wish to add a plant to, you’ll need a grow light.
To grow your own P. microphylla, you’ll need to start from seed, take a stem cutting from an existing plant, divide an existing plant, or purchase a nursery start.
Outdoors, this is a vigorous self-sower that disperses tiny seeds with gusto, contributing to its invasive tendencies.
However, starting from seed may pose a challenge, as most retailers sell live plants and seeds can be hard to come by.
The artillery plant also known by its scientific name Pilea microphylla, is a popular and easy-to-care-for houseplant. Its charm lies in its delicate green leaves creeping habit, and interesting method of dispersing pollen. To keep your artillery plant looking its best, it’s important to clean it regularly. In this comprehensive guide, we’ll cover everything you need to know about effectively cleaning an artillery plant.
Why Regular Cleaning is Essential
Cleaning your artillery plant serves multiple important purposes:
-
Removes dust, dirt, and debris – Dust and debris that collects on the leaves can block sunlight, inhibiting photosynthesis and growth Cleaning helps maximize light absorption
-
Deters pests – Dust attracts pesky bugs like spider mites. Regular cleaning reduces places where they can hide and thrive.
-
Prevents disease – Bacteria and fungi can grow on dusty leaves, especially in humid conditions. Cleaning minimizes spread of contagions.
-
Improves appearance – Dusty leaves look dull. Cleaning makes the leaves shiny and vibrant.
When to Clean Your Artillery Plant
Ideally, artillery plants should be cleaned at least once a month. More frequent cleanings may be needed for plants kept in dusty areas or prone to pests Signs it’s time for a cleaning include
- Visible dust/dirt accumulation
- Presence of webs or bugs
- Yellow, spotted leaves
- Lackluster appearance
Seasonally, it’s best to clean the plant more often in spring and summer when dust and pests are more prevalent. Reduce cleaning frequency in fall and winter when plant growth slows.
Supplies Needed
Cleaning an artillery plant is a simple process. You don’t need any specialized equipment. Recommended supplies:
- Soft cloth, sponge, or cotton pads
- Small container of lukewarm water
- Mild, plant-safe soap (optional)
- Clean spray bottle
- Tweezers or q-tips (for pests)
Avoid rough materials like brushes that could damage the delicate leaves.
Step-by-Step Cleaning Instructions
Follow these steps to clean your artillery plant:
1. Check for Pests
Before cleaning, inspect the plant closely for signs of bugs like spider mites, mealybugs, or aphids. Also look for any visible webbing. If pests are present, you’ll need to take extra steps to remove them.
2. Remove Loose Dirt
Use a soft paintbrush or makeup brush to gently brush off any loose dirt or debris. Avoid being too rough.
3. Make Cleaning Solution
Fill your spray bottle with lukewarm water. If needed, add a drop or two of mild, plant-safe liquid soap. Avoid harsh chemicals.
4. Mist the Leaves
Lightly mist the leaves with the cleaning solution to soften any stuck-on dust and grime. Ensure coverage of both top and undersides of leaves.
5. Wipe Down Leaves
Gently wipe each leaf with a soft cloth or cotton pad dampened with the cleaning solution. Wipe from the base of the leaf outward to the tip.
6. Check for Pests Again
During wiping, inspect again for any pests that may be present. Use tweezers or q-tips dipped in alcohol to remove small bugs. For severe infestations, use insecticidal soap.
7. Rinse if Needed
If soap was used, rinse the leaves with clean water to remove residue. Allow excess water to drain before returning the plant to its spot.
8. Isolate if Infested
If one plant is infested with pests, isolate it from other plants to prevent spread.
And that’s it! With this thorough cleaning routine, your artillery plant will look lush and pest-free.
Extra Artillery Plant Cleaning Tips
- Use distilled or rain water rather than tap water if possible.
- Wipe leaves with a microfiber cloth to avoid damage.
- Mist leaves before wiping to loosen stuck-on debris.
- Avoid flower and leaf shine products which can damage plants.
- Inspect new plants closely before bringing them home.
- Keep plant away from air vents to minimize dust buildup.
- Group plants together to create humidity and deter pests.
- Ensure the plant has adequate airflow and light.
- Repot annually in fresh potting mix.
- Fertilize monthly in the growing season for healthy growth.
- Prune off any dead or damaged leaves.
- Monitor closely and act fast at any signs of pests/disease.
What Makes Artillery Plants So Dust-Prone?
Artillery plants are especially prone to collecting dust for a few reasons:
- Tiny leaves have lots of surface area for dust to cling to.
- Fuzzy leaf texture traps debris.
- Low-growing nature puts leaves closer to the dust zone.
- Rapid growth results in lots of new dust-catching leaves.
- Preferred bright, warm spots correlate with dustier areas.
Due to these factors, vigilant cleaning is required to keep artillery plants looking their best!
Potential Problems from Unclean Plants
Neglecting cleaning can lead to several issues for artillery plants:
-
Spider mites – One of the most common pests, evidenced by fine webs and speckled leaves.
-
Mealybugs – Cottony insects that leave sticky residue on foliage.
-
Scale insects – Hard bumps that form on leaves and stems.
-
Aphids – Tiny sap-sucking green bugs that distort growth.
-
Powdery mildew – White fungal coating that thrives on uncleaned leaves.
-
Stunted growth – From impeded photosynthesis and pest damage.
-
Leaf drop – Due to pests, diseases, or poor air circulation.
Catching problems early by regular cleaning gives you the best chance to treat issues before lasting damage occurs. An ounce of prevention is worth a pound of cure!
Alternative Cleaning Methods
If you want to avoid using soap on your artillery plant, here are some alternative cleaning solutions:
-
Milk – The proteins in milk work to kill many varieties of powdery mildew. Wipe leaves with a cloth dipped in milk.
-
Water and vinegar – A 50/50 mixture of water and white vinegar helps remove hard water deposits and shine leaves.
-
Hydrogen peroxide – Diluted hydrogen peroxide solutions can reduce fungal growth and kill larvae. Use care not to overdo it.
-
Neem oil – This organic oil has natural antifungal and pesticidal properties without harsh chemicals.
-
Dish soap – A mild plant-safe soap is an effective cleaner in moderation. It also breaks down waxy pest coverings.
-
Isopropyl alcohol – Wiping leaves with 70% isopropyl alcohol kills many soft-bodied insects on contact.
Always test any solutions on a small area first and adjust concentrations as needed. Less is often more when it comes to cleaning delicate plants like the artillery plant.
Set a Routine for Plant Health
Caring for houseplants is much easier when you establish a consistent routine. Here is a sample weekly schedule that ensures your artillery plants thrive:
-
Daily – Check soil moisture and water if needed. Mist leaves if dry.
-
2-3 Times Per Week – Wipe dust off leaves or rinse if visibly dirty.
-
Weekly – Apply fertilizer according to package directions.
-
Monthly – Thoroughly clean leaves. Repot if rootbound.
-
Quarterly – Inspect closely for pests and treat any found accordingly. Prune leggy growth.
Customize this schedule based on your plant’s specific needs. The most important thing is to not let too much time lapse between cleanings.
From a Stem Cutting
If you know someone with a plant already, you can get a head start by taking a cutting.
To propagate a stem cutting, make your cut about four inches from the tip of a growing stem at any time during the spring or summer.
Use clean shears and choose a spot to cut that’s just below a leaf node. This is a natural growing point, where roots will readily sprout.
Pinch off the lower leaves to reveal a bare stem about two inches long.
Place the bare stem in one inch of water in a narrow container that can support it, like an old unused drinking glass. There should be no leaves below the water line, as they will start to decay and foul the water.
Place the glass in a location with bright indirect sunlight, such as near a window with an opaque curtain. Avoid direct sunlight, as it may burn the foliage and roots with its intensity.
Change the water daily.
When roots sprout over the next couple of weeks, you’ll have a cutting that’s ready to pot up, which we’ll discuss shortly.
In addition to calling upon another gardener to assist you with the cutting method to get started with your first plant, you may be lucky enough to have a friend who is getting ready to repot. In this case, you can ask for a division.
This method involves unpotting and dividing one plant into two or more sections and transplanting the sections to their own containers.
You can learn how to divide an herbaceous perennial in our guide.
If you haven’t got a repotting friend, it’s time to get your wallet out.
From a Nursery Start/Transplanting
When you buy a pilea, it may be very young or more mature. To transplant it to another container, or to pot up a stem cutting or division, do the following:
Choose a vessel that is large enough to accommodate the plant, whatever its size, with two to three inches of growing room all around it. Be sure that it has one or more drainage holes.
Keep in mind that when it’s mature, this type of pilea may be between 12 and 24 inches wide. You will probably need to repot more than once before maturity and may want to keep the early containers on the inexpensive side.
At maturity, you may opt to select a hanging container to showcase the species’ creeping, trailing nature.
Buy potting soil that’s rich in organic matter, moisture-retentive, loose and airy, and well-draining. It will approximate the 5.0 to 6.0 pH that this tropical species prefers.
Place a single layer of pea gravel in the bottom to facilitate drainage, and then fill the vessel about halfway with potting soil.
Gently unearth the plant from its current pot.
Settle it in the potting medium so it sits at the same depth it was in the original container.
Backfill with soil and tamp it very lightly to hold the plant upright. Take care not to compact the soil. Light and airy is what you want to aim for.
If you are potting a rooted stem cutting, settle it in the soil, taking care not to injure the fledgling roots.
Bury the rooted end one inch deep in soil, tamp lightly and loosely backfill.
To transplant a division, you’ll want to settle it in much the same way, with about an inch of soil over the roots, at about the same height it was in its original vessel.
After potting, water until it runs out the bottom of the vessel, and repeat.
When all drainage has stopped, find a location with bright, indirect light. You may want to place the container on a single layer of pea gravel in a shallow, non-rusting pan. Add water to the pan until it comes just to the top of the gravel.
This is a great way to increase ambient humidity and replicate the natural habitat of a pilea plant.
One final note: With stems that are fleshy like a succulent, it’s easy to bruise or break them, so be sure to handle yours with care.
Once potted and watered, it’s time to apply a half-strength liquid or slow-release granular houseplant food. It’s best to apply this to wet soil to avoid burning tender roots and stems.
Feed again in the summer, and continue to feed once in spring and once in summer going forward.
Some gardeners recommend feeding more frequently, but overfeeding may prove to be a disaster resulting in a visible buildup of salts on the soil and container that inhibits water uptake.
In the event of a buildup, flush the pot through several times with water, and reduce feeding to once a year in the spring.
Keep the soil evenly moist by watering when the surface feels dry. Avoid oversaturation, as the roots rot easily, and reduce watering during winter dormancy. Just don’t let the pot completely dry out.
In addition, avoid wetting the leaves, especially in low-light locations, to avoid creating a breeding ground for the bacterial and fungal diseases we’ll discuss shortly.
P. macrophylla is not hard to grow when you remember to:
- Use an organically-rich potting soil that is loose, well-draining, and moisture-retentive.
- Avoid packing the soil down hard when potting. Instead, tamp loosely and leave lots of air holes to facilitate the flow of nutrients, oxygen, and water.
- Fertilize sparingly to avoid a buildup of salts, and flush several times as needed in the event of overfeeding.
- Maintain even moisture without oversaturation by watering when the soil surface feels dry.
This is an easy species to maintain. For a more compact shape, pinch off a few inches of the growing tips. If you like, use them to make new plants per the propagation instructions above.
If a fragile stem breaks, use clean pruners to remove the damaged portion. Be sure to cut just above a leaf node to encourage rapid regeneration.
Also, tap water is sometimes so alkaline or “hard” that it causes white spots to form on the leaves. If you note this issue, switch to distilled water.
Like many houseplants of tropical origin, P. microphylla thrives in bright, indirect light but it can tolerate a low-light placement.
Photo by Daderot, Wikimedia Commons, via
P. microphylla ‘Variegata’ is a variegated pink and white cultivar you may like to choose for a location with bright indirect light.
P. microphylla ‘Variegata.’ Photo by Forest & Kim Starr, Wikimedia Commons, via
For best results in low light, remember that a green variety is your best bet, as a variegated one is likely to shade to dark green anyway.
This species has not been widely developed, and options and availability are currently not extensive.
Pilea Microphylla Artillery plant care & Tips.
FAQ
How do you take care of an artillery plant?
Why is my artillery fern turning brown?
Why is my artillery plant dying?
How to get rid of artillery weeds?