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Beginner Guide

Soil & Composting

Healthy soil is the foundation of a productive garden. Learn about soil types, how to test and amend your soil, and how to make nutrient-rich compost.

18 min read
Foundation knowledge

Feed the Soil, Not Just the Plants

Great gardens start with great soil. While it's tempting to focus on fertilizers and plant varieties, the most successful gardeners know that building healthy soil is the key to growing healthy plants year after year.

Healthy soil is alive—teeming with bacteria, fungi, earthworms, and countless other organisms that break down organic matter, cycle nutrients, and create the structure plants need to thrive. Your job is to feed and protect this living system.

Understanding Your Soil Type

Grab a handful of moist soil and squeeze it. Sandy soil falls apart, clay holds its shape and feels sticky, and loam holds together but crumbles when poked.

Soil pH: The Key to Nutrient Availability

Soil pH affects how well plants can absorb nutrients. Most vegetables prefer slightly acidic soil (pH 6.0-6.8). Test your soil with a home kit or send a sample to your local extension service.

pH RangeLevelBest For
4.5-5.5Strongly AcidicBlueberries, potatoes
5.5-6.0Moderately AcidicPeppers, sweet potatoes
6.0-6.5Slightly AcidicMost vegetables (ideal range)
6.5-7.0NeutralBrassicas, beans, beets
7.0-7.5Slightly AlkalineAsparagus, spinach

To Raise pH (more alkaline):

  • • Add garden lime (calcium carbite)
  • • Apply wood ash sparingly
  • • Use dolomitic limestone

To Lower pH (more acidic):

  • • Add elemental sulfur
  • • Use acidic mulches (pine needles)
  • • Apply coffee grounds

Making Compost: Black Gold for Your Garden

Compost is decomposed organic matter that improves soil structure, adds nutrients, and feeds beneficial soil organisms. It's the single best thing you can add to your garden.

Greens (Nitrogen)
  • Grass clippings
  • Vegetable scraps
  • Coffee grounds
  • Fresh plant trimmings
  • Fruit waste
  • Manure (herbivore only)
Browns (Carbon)
  • Dry leaves
  • Straw or hay
  • Cardboard (shredded)
  • Wood chips
  • Paper (non-glossy)
  • Dried plant stalks
Never Compost
  • Meat and bones
  • Dairy products
  • Diseased plants
  • Weeds with seeds
  • Pet waste
  • Treated wood
  • Coal ash
1Choose Your Location

Find a convenient spot with good drainage.

  • Partial shade is ideal (prevents drying)
  • Easy access for adding materials
  • Near a water source for moistening
  • On bare soil or use a compost bin
  • At least 3'x3'x3' for hot composting
2Build Your Pile

Layer browns and greens for optimal decomposition.

  • Start with a 4-6" layer of browns (carbon)
  • Add 2-3" layer of greens (nitrogen)
  • Repeat layers until pile is 3' high
  • Aim for 3:1 browns to greens ratio by volume
  • Add water - pile should feel like wrung sponge
3Maintain the Pile

Regular attention speeds decomposition.

  • Turn pile every 1-2 weeks for hot composting
  • Or leave alone for 6-12 months (cold composting)
  • Keep moist but not soggy
  • Add new materials in center of pile
  • Hot piles should reach 130-160°F
4Harvest Your Compost

Finished compost is dark, crumbly, and earthy-smelling.

  • Ready in 2-3 months (hot) or 6-12 months (cold)
  • Should not resemble original materials
  • Screen out unfinished pieces
  • Use immediately or store in covered bin
  • Apply 1-3" to garden beds annually

Soil Amendments

Compost

Improves structure, adds nutrients, feeds soil life

Application: 1-3 inches annually, work into top 6 inches

Aged Manure

High in nitrogen, improves soil structure

Application: Apply in fall, never use fresh on edibles

Leaf Mold

Excellent water retention, improves structure

Application: 2-3 inches as mulch or worked into soil

Worm Castings

Concentrated nutrients, beneficial microbes

Application: Handful per plant or brew into compost tea

Cover Crops

Adds organic matter, fixes nitrogen (legumes), prevents erosion

Application: Plant in fall, cut and incorporate in spring

Wood Ash

Raises pH, adds potassium and calcium

Application: Light dusting, never on acid-loving plants

Next Steps