Soil & Potting: The Foundation of Plant Health
The right soil makes everything easier—watering, feeding, root health. Learn what goes into a good potting mix and how to match soil to your plants.
Soil Components Explained
Understanding what each ingredient does helps you create the perfect mix.
Peat Moss / Coco Coir
Moisture retention, organic matter
Holds water and nutrients while remaining light. Coco coir is a sustainable alternative to peat.
Used in: Most potting mixes, moisture-loving plants
Perlite
Drainage, aeration
White volcanic glass that creates air pockets. Prevents soil compaction and improves drainage.
Used in: Almost all mixes, especially for tropical plants
Pumice
Drainage, structure
Like perlite but heavier and doesn't float. Excellent drainage, won't break down.
Used in: Succulent mixes, long-term plantings
Orchid Bark
Aeration, drainage
Chunky pieces that create large air spaces. Breaks down slowly over time.
Used in: Orchids, aroids (Monstera, Philodendron), epiphytes
Vermiculite
Moisture retention
Holds water more than perlite. Good for seed starting and moisture-loving plants.
Used in: Seed starting, African Violets, ferns
Sand (Horticultural)
Drainage, weight
Improves drainage and adds weight to prevent tipping. Use coarse sand, not beach sand.
Used in: Cacti/succulent mixes, heavy top plants
Activated Charcoal
Odor control, filtration
Absorbs impurities and helps prevent root rot. Not essential but beneficial.
Used in: Terrariums, closed containers
Worm Castings
Nutrients, beneficial microbes
Natural fertilizer that improves soil biology. Rich in nitrogen.
Used in: As amendment to any mix (5-10%)
DIY Soil Recipes
Mix your own for better results than store-bought mixes.
All-Purpose Houseplant Mix
Pothos, Philodendron, Peace Lily, most tropical foliage
Recipe
- 2 parts potting soil
- 1 part perlite
- 1 part orchid bark
Notes
A great starting point for most houseplants. Well-draining but retains some moisture.
Aroid Mix
Monstera, Philodendron, Alocasia, Anthurium
Recipe
- 2 parts orchid bark
- 1 part perlite
- 1 part potting soil
- 1 part horticultural charcoal
Notes
Very chunky and airy. Mimics the loose debris aroids grow in naturally.
Succulent/Cactus Mix
All succulents, cacti, Jade Plant, Aloe
Recipe
- 2 parts potting soil
- 2 parts coarse sand or pumice
- 1 part perlite
Notes
Drains very quickly. Can be even grittier for desert cacti.
African Violet Mix
African Violets, Begonias, Gloxinia
Recipe
- 2 parts peat moss or coco coir
- 1 part perlite
- 1 part vermiculite
Notes
Light and moisture-retentive but still drains well.
Orchid Mix
Phalaenopsis and other epiphytic orchids
Recipe
- 3 parts orchid bark
- 1 part perlite
- 1 part sphagnum moss
Notes
Roots need air! This is barely "soil" at all—more like a mounting medium.
Choosing the Right Pot
Terracotta
Pros
- Porous - helps soil dry
- Heavy - stable
- Classic look
- Affordable
Cons
- Dries quickly in dry climates
- Breakable
- Salt buildup on exterior
Best for: Succulents, cacti, plants prone to overwatering
Ceramic (Glazed)
Pros
- Attractive designs
- Retains moisture better
- Easier to clean
Cons
- Heavier
- More expensive
- No breathability
Best for: Moisture-loving plants, decorative focal plants
Plastic
Pros
- Lightweight
- Inexpensive
- Retains moisture
- Won't break
Cons
- Can look cheap
- May become brittle
- No breathability
Best for: Large plants, hanging plants, nursery use
Fabric/Grow Bags
Pros
- Excellent aeration
- Prevents root circling
- Foldable storage
Cons
- Dries quickly
- Not decorative
- Can be unstable
Best for: Large plants, vegetables, air-pruning benefits
Why Drainage Matters
Roots need oxygen as much as water
Standing water leads to root rot
Drainage holes let excess water escape
Without drainage, it's nearly impossible to water correctly
Always choose pots with drainage holes, or use the cachepot method.
Frequently Asked Questions
Can I use garden soil for houseplants?
No—garden soil is too dense and heavy for pots. It compacts over time, holds too much water, and may contain pests, weed seeds, or diseases. Always use potting mix made for containers.
How often should I replace potting soil?
Soil breaks down over 1-2 years, losing structure and nutrients. Repot with fresh soil when you size up, or refresh the top few inches annually. Signs it's time: soil stays soggy, compacts hard, or develops a crust.
What if my pot doesn't have drainage holes?
Either drill holes (possible with ceramic, terracotta) or use it as a cachepot—put the plant in a plastic nursery pot inside the decorative pot. Remove to water and let drain before returning.
Should I put rocks at the bottom for drainage?
No! This is a myth. Rocks actually raise the water table and keep roots wetter. The best "drainage layer" is having drainage holes and using well-draining soil throughout.
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