Garden soil and compost

Learn what the latest research tells us about common compost or soil questions and how to put that knowledge into practice in your garden.

How to Use Compost in Gardens and Landscapes

By Weston Miller and Jeremiah Mann

Compost is a soil amendment consisting of partially broken-down organic material. Use compost to improve soil for vegetable gardens, landscape areas and lawns. Learn how to apply the correct amount of compost and how to avoid common compost mistakes.

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Photo Credit: Markus Spiske - Unsplash.com (Cropped from original)

Latest Resources

Can I use coffee grounds for mulch without attracting bears or cougars?

Q: I'd like to use my organic light roast coffee grounds to mulch my acid loving landscape plants, but I have read that bears love coffee grounds. We have deer, bears and cougars where I live. Is this known to be true or am I safe to use the grounds without baiting bears or other critters?

A: View answer | View all featured questions

How to take a soil sample 101

Come along with Logan and learn how to take soil samples from your garden or field beds.

Logan Bennett | Jan 2025 | Video

Can pine needles be used as mulch for fruit and maple trees?

Q: Is it OK to mulch fruit trees and maple trees with pine needles or are they too acidic?

A: View answer | View all featured questions

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Latest News

Clueless about compost? Here are timely tips

Use the 'one-third' system for easy composting

Kym Pokorny | Nov 4, 2024 | News story

Rhododendrons and azaleas need a strong acidic soil

The most effective way to correct an iron deficiency for these plants is to acidify the soil.

Jun 4, 2024 | News story

Add organic matter to improve garden soils

Good organic amendments for garden soils include wood by-products such as sawdust and bark mulch, rotted manure, grass or wheat straw and compost.

Feb 27, 2024 | News story

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Become a Master Gardener!

The Master Gardener™ program educates Oregonians about the art and science of growing and caring for plants. This program also facilitates the training of a highly educated group of volunteers, who extend sustainable gardening information to their communities through education and outreach programs.

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Compost Resources

Herbicide-Contaminated Compost and Soil Mix: What You Should Know — and What You Can Do About It

Compost and soil mix products sometimes contain herbicide residue. This residue can damage certain vegetable, fruit and flower crops. The residue likely comes from contaminated hay, grass clippings or manure. Watch ...

Weston Miller, Kaci Buhl | Feb 2021 | Extension Catalog publication Peer reviewed (Orange level)

Don’t worry, maggots help break down compost pile

Soldier fly larvae are voracious consumers of high nitrogen materials such as kitchen food scraps and manures, as they decay.

Kym Pokorny | Aug 19, 2022 | News story

Compost tumbler suggestions?

Q: Looking to buy one but would like your opinion for easiest use and quality if you have a preference.

A: View answer | View all featured questions

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How to Collect a Soil Sample for Testing

In this video, Dennis Brown, OSU Extension Master Gardener volunteer, Portland Metro Area, demonstrates how to take a soil sample in the garden. Video courtesy of Dennis Brown and Dave Meeker.

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Photo Credit: Dylan de Jonge - Unsplash.com (Cropped from original)

Soil Resources

How do I test my garden soil?

Learn why you should test your garden soil and the different kinds of tests to ask for. Resources include instructions for how to collect a soil sample for testing and a short video demonstration.

Brooke Edmunds | Apr 2021 | Article Peer reviewed (Gray level)

Understanding Soil Health and Biota for Farm and Garden

Like sunlight, water and air, soils are the foundation of life on Earth. Learn how soils link plants, the atmosphere, agriculture, food security, health, the economy and the environment.

Shikha Singh, Linda Brewer, Scott Lukas | Jun 2023 | Extension Catalog publication Peer reviewed (Orange level)

Clay soil challenges and solutions for Oregon gardeners

Bark, manure, leaf mold and compost are among the organic amendments commonly used to improve clay soil.

Kym Pokorny | Feb 5, 2022 | News story

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Can I use coffee grounds for mulch without attracting bears or cougars?

A: View answer | View all featured questions

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