Southern Magnolia 'Edith Bogue/Brown Velvet' in Philadelphia: Zone 6 Hardiness, Growth, and Fertilization

Philadelphia (Zone 6b/7a) homeowner planted 'Edith Bogue/Brown Velvet' magnolia in July. Asks about winter survival, growth rate, bud behavior, and fertilizer spikes vs. granular.

Hardiness & Winter Survival

'Edith Bogue' and 'Brown Velvet' are Zone 6 cultivars. Philadelphia winters are within range. Mulch 3 inches, water until freeze, wrap young trees first 2–3 winters with burlap screen (not tight wrap) on south/west sides.

Growth Expectations

• Rate: Moderate (1–2 ft/year in Zone 6 vs. 2–3 ft in South).
• Form: Upright pyramidal; 30–50 ft tall, 15–25 ft wide at maturity.
• Roots grow in winter; shoots do not.

Bud Behavior

Visible buds in fall = leaf buds (overwinter, expand spring). Flower buds form in spring, bloom early summer.

Fertilization: Granular > Spikes

• Broadcast 10-10-10 at 1 lb/inch trunk diameter (spring + late summer).
• Water in thoroughly.
• Spikes concentrate salts, distribute unevenly, cost more. OK for very small trees only.

Organic Option

Composted manure or Holly-tone (acid-forming) at label rates. Magnolias prefer slightly acidic soil (pH 5.5–6.5).

With winter protection and proper feeding, this magnolia will thrive in Philadelphia.