Fertilize Responsibly

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Start plants right – with compost

Fertilizers can pollute our waterways and damage soil and plant health when overused. The best start for all plants is to amend the soil with compost before planting.

Trees, shrubs, and most perennials get all the nutrients they need from healthy soil provided with regular compost and mulching with organic matter like leaves, or wood chips. If plants aren’t doing well, call the Garden Hotline to diagnose the need – it may be a soil problem, disease, or a nutrient need.

Need fertilizer? Go natural!

Lawns, flowers, and gardens sometimes need extra nutrients. Look for the words “Natural organic” or “Slow-release” on the fertilizer bag. Nutrients are released slowly by soil organisms, feed plants longer, and are less likely to wash off into streams.

  • Lawns: Use a natural fertilizer with a 3-1-2 formula (3 parts nitrogen, 1 part phosphorus, 2 parts potassium) or that same ratio of nutrients (6-2-4, 12-4-8 etc.). Fertilize lawns in the fall (September-October) at a rate of 1 lb. nitrogen per 1000 square feet of lawn. Every few years spread lime in the fall or spring too. Grasscycling (mulch mowing) returns free nutrients every time you mow.
  • Annuals and vegetable gardens: Use a balanced “natural organic” fertilizer, such as 5-5-5 or 10-10-10 formula that contains other micro-nutrients as well. Add lime every few years. Get a soil test if plants aren’t doing well, to find out what nutrients are needed.
  • Trees, shrubs, and perennials: Use a low-phosphorus fertilizer if necessary. Organic mulches can provide most nutrient needs.

Reality check – get a soil test

Using too much fertilizer, or the wrong kind,can damage plants and streams. Call the Garden Hotline to diagnose plant problems, pick the right fertilizer, and to learn how to get an inexpensive soil test that will tell you what’s really in your soil, and what your lawn or garden needs.

More Information

Growing Healthy Soil guide (pdf)

Questions? Call the Garden Hotline at (206) 633-0224 or email help@gardenhotline.org