• Molly's Pumice 3 quart (3.3 L) bag, screened 3/8 to 1/2 inch (8 to 12 mm)
  • A 3 quart bag of Molly's Pumice fills about eight 4-inch pots
  • Pumice beside a ruler and a quarter, screened to 8 to 12 mm
  • A handful of screened, low-dust pumice
  • Pumice used for rooting cuttings, propagation boxes and hydroponic growing
  • Pumice mixed into potting mix for a custom blend
  • Pumice as a drainage layer at the base of a pot
  • Molly's Pumice resealable stand-up bag
  • Molly's Pumice bag on a bed of pumice
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Molly's Pumice - Screened 8-12 mm Pumice for Custom Blends, Top Dressing and Specialty Plant Projects

Molly's Pumice - Screened 8-12 mm Pumice for Custom Blends, Top Dressing and Specialty Plant Projects

$22.99 USD
$22.99 USD
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  • Soil-free component, 100% single material.

Quick answer: what is Molly's Pumice?

  • What it is: natural, lightweight porous volcanic rock, screened to 8 to 12 mm (3/8 to 1/2 in) and packed low dust.
  • For: custom mixes for aroids, succulents, cacti and bonsai, plus propagation, top dressing and drainage layers.
  • In the bag: 100% pumice, 3 dry quarts (3.3 L), in a resealable stand-up bag. Fills about eight 4-inch pots.
  • Screened grade. Excess dust, powder and fines are screened out for a consistent particle size.
  • A single component, not a potting mix. For a ready-to-use blend, choose one of Molly's potting mixes.

Pumice is a natural, lightweight volcanic rock, formed when gas is trapped in cooling lava and leaves small holes behind. That porous structure holds moisture and releases it slowly to roots. Molly's Pumice is 100% natural, with no dyes, additives or fillers.

Use Molly's Pumice to build a mix around what your plants need. It's screened to remove excess dust and to a consistent 3/8 to 1/2 inch (8 to 12 mm) size, which gives you more control over structure, drainage and aeration. With aroids and other tropicals it helps prevent compaction in a chunky mix; with succulents, cacti and bonsai it builds a gritty, fast-draining mix. Its bright white color also makes a clean top dressing against green foliage.

Why growers choose it

  • Consistent 3/8 to 1/2 inch (8 to 12 mm), low dust. Screened to remove excess dust, powder and fines, for a clearly stated coarse grade and a predictable particle size.
  • Good value. A 3 quart (3.3 L) bag fills about eight standard 4-inch pots. The resealable bag stands up, so it's easy to pour and store.
  • Drainage and root airflow. Porous pumice adds lasting structure to potting mixes, creating drainage and air space around roots without compacting like fine soil-based media. It also works as a drainage layer in pots and terrariums.
  • For aroids, succulents, cacti and bonsai. Use with your potting mix or blend with other components for monstera, philodendron, alocasia, succulents, cacti and bonsai.
  • Propagation and top dressing. Root cuttings in pumice or in propagation boxes, or use it in hydroponic growing. As a top dressing it gives a finished look and helps keep potting mix in place.

How to use

  • For custom mixes, blend it into your own mixes for aroids, succulents, cacti, bonsai and other plants that like a chunky or gritty mix.
  • For propagation, root cuttings in rinsed pumice and keep it lightly moist.
  • For top dressing, add a thin layer to the surface of the pot for a clean, finished look.
  • Rinse before use if you want to remove any remaining fine dust.

Specifications

  • Material: 100% pumice
  • Particle size: 8 to 12 mm (3/8 to 1/2 in), screened
  • Bag size: 3 dry quarts (3.3 L), filled by volume
  • Coverage: about eight standard 4-inch pots (varies with pot shape and use)
  • Packaging: resealable stand-up bag

Where it fits with Molly's mixes

Molly's potting mixes are ready to use and already blended for air, moisture and drainage, so you don't need to add anything to them. Molly's soil-free components are single materials for growers who want more ways to grow, propagate and customize. For a complete mix, see Molly's Aroid Mix, Molly's Succulent Mix or Molly's Orchid Mix.

Frequently asked questions

What size is Molly's Pumice?
It's screened to 3/8 to 1/2 inch (8 to 12 mm). Screening also removes excess dust, powder and fines for a more consistent size.
How is pumice different from perlite?
Both are volcanic. Perlite is volcanic glass that is heated until it expands, which makes it very light. Pumice is a natural porous rock, so it is heavier and holds its shape.
Is it dusty when I open it?
It's screened before packing to remove excess dust, powder and fines. A little dust can settle at the bottom of the bag as the stones rub together in transit. Rinse before use if you want to remove it.
What plants is it best for?
Houseplants, tropicals and aroids such as monstera, philodendron and alocasia, where it helps prevent compaction and builds a chunky, airy mix. It also suits succulents, cacti and bonsai, where it builds a gritty, fast-draining mix.
How much moisture does pumice hold?
Pumice is porous, so it holds some moisture in its pores and releases it slowly. How much a mix holds depends on how much pumice you use.
How do I mix it with soil?
Put your chosen amounts of pumice and potting medium in a bucket at least twice the size of the finished volume, then mix with a trowel or your hands until the texture is even.
Can I use it outdoors?
Yes. Blend it into potting soil to help prevent compaction and add aeration and drainage, or use it as a drainage layer in outdoor planters, a top dressing for an outdoor succulent bowl, or a mulch with a contrasting white color. Pumice is heavier than perlite, so it's less likely to blow or float away.
Can it be reused?
Yes. Pumice is durable and long-lasting. Clean it thoroughly before you reuse it with a different plant.
How many pots does a bag fill?
About eight standard 4-inch pots. It varies with how you use it: top dressing, drainage layer or mixed in.
Do I need to add pumice to Molly's mixes?
No. Molly's Aroid, Succulent and Orchid mixes are complete and ready to use. Pumice is for mixes you make yourself, propagation, top dressing and drainage layers.

Care and handling: Not for consumption. Keep out of reach of children and pets. Store dry.

WARNING: This product can expose you to chemicals including crystalline silica, which is known to the State of California to cause cancer. For more information go to www.P65Warnings.ca.gov.

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