Milorganite vs. Composted Manure: Which Is Better for Flower Beds?

Evaluating Milorganite as a Soil Amendment

Milorganite is a fertilizer made from treated sewage sludge. While it provides nutrients, concerns remain about potential pharmaceutical and heavy metal residues. Composted cow or horse manure is a safer, more effective alternative for building soil health.

Using Composted Manure

• Till planting areas and spread 2–3 inches of composted manure.
• Work it into the top 6–8 inches of soil.
• Side-dress plants annually to maintain fertility.
• Wear gloves and wash hands after handling.

Mulching and Drainage

After planting seeds, apply a light mulch (straw, pine needles) to retain moisture without smothering seedlings. If soil stays soggy more than a day, improve drainage with organic matter or choose a better-drained site—most plants dislike "wet feet."