Stabilizing a Collapsing Hillside: Need More Site Details

You have a large hill behind your home that collapsed several times after disturbance during construction. It’s not all clay but contains clay. Grass grows but doesn’t hold the slope. You’re re-excavating and want planting suggestions to prevent future failure.

Information Needed for Specific Advice

• Hill height and approximate angle of incline.
• Aspect (north, south, etc.) and sun exposure (shaded by trees or structures?).
• What exactly is the excavation doing?

With these details, I can recommend deep-rooted, soil-binding plants and any needed engineering measures.