Most gardens contain a problem area or two. A slope is a problem area in a chicken garden because chickens love a slope and gravitate toward it, continually scratching and creating dirt baths in that area. A barren slope is open to soil erosion and loss of soil nutrients.
If you need a fix for a slope, consider these plants:
California wild lilac
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Ceanothus. Evergreen shrubs and groundcover. Zones 8–10. Easy care, drought tolerant. Beautiful spring-blooming flowers.
Honeysuckle
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Lonicera japonica. Deciduous vines. Zones 4–11. Fragrant showy flowers. Especially good for ground cover erosion control. Honeysuckle can be valuable in a chicken garden, but it has known toxic qualities to chickens. Chickens generally avoid it in free-ranging situations. Never feed it directly to your chickens.
Ice plant
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Malephora. Succulent perennials. Zones vary by species. Durable perennial for heat, winds, and fire. Drought tolerant. Low maintenance. Plants bloom over a long time.
Western sword fern
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Polystichum munitum. Zones 3–8. Most common fern of Western forests. Beautiful, long, lush, dark green fronds. Partial or full shade.