Boxwood & Knockout Rose Bed: Fixing Drainage & Spacing After Fertilizer Overdose

Gardener planted 10 Knockouts in Miracle-Gro soil + Bloom Booster (high phosphorus). Roses pink, not red; buds poor. Heavy rain. Expert said: replant in compost-only holes, water heavily to flush salts. Follow-up: 240 sq ft bed along driveway, puddles when rains. Wants boxwood border + Knockout row. Asks: will raised bed fix drainage? Spacing?

Drainage: Raised Bed Alone Won't Fix Puddling

Install 4-inch perforated drain pipe in 24-inch deep trench down bed center, bedded in coarse sand. Cheap, effective.

Spacing

• Boxwood: Plant 8" from driveway edge. Space at mature width (e.g., 12" wide variety = 10" apart).
• Knockouts (3-gal): Mature 3×3 ft (Zone 6). Alternate sides of drain pipe: 4 ft apart, staggered. In warm winters, may reach 4 ft—prune hard in spring.

Boxwood Resource

VT Boxwood Guide