Magnolia ‘Susan’

Magnolia 'Susan' is a deciduous hybrid magnolia grown as a large shrub or small tree. It is part of the National Arboretum’s “Little Girl” series and is known for late-blooming, fuchsia to purple-red flowers.

Magnolia 'Susan' typically reaches about 8–12 feet tall and wide, although some plants may grow larger in favorable conditions. Its naturally multi-stemmed form can be maintained as a shrub or trained into a small tree.

Magnolia 'Susan' is deciduous, so it loses its leaves in fall and remains bare through winter. The bare branches and fuzzy flower buds provide some winter interest.

Magnolia 'Susan' is generally hardy in USDA Zones 4–8. Flower buds can still be damaged by unusually late freezes, especially when spring warms early.

Plant Magnolia 'Susan' in full sun to partial shade, with roughly four or more hours of direct sunlight for the best flowering. In hot climates, light afternoon shade can reduce heat and drought stress.

Choose a sheltered location with well-drained, organically rich soil and enough room for an 8–12-foot shrub or small tree. Avoid exposed windy sites and warm south-facing locations that can trigger premature flowering.

Magnolia 'Susan' can tolerate clay soil if it drains adequately and is enriched with organic matter. Avoid sites that stay waterlogged, because saturated soil can damage its roots.

Magnolia 'Susan' grows best in slightly acidic to neutral soil that is organically rich and moisture-retentive. It may tolerate somewhat broader soil conditions, but persistent alkalinity can contribute to nutrient problems.

Provide moderate, even moisture, especially during the first few growing seasons and during drought. Water deeply when the upper soil begins to dry, then apply mulch to help stabilize soil moisture.

Common causes include insufficient sunlight, drought stress, excessive nitrogen, immature plants, or flower buds damaged by frost. Magnolia 'Susan' blooms on older wood, so severe pruning can also remove the next season’s flower buds.

Brown leaves are often caused by drought, root stress, wind, heat, transplant shock, or leaf-spot diseases. Check soil moisture and drainage first, and avoid keeping the root zone constantly saturated.

Yes, apply a 2–3-inch layer of organic mulch over the root zone to conserve moisture and moderate soil temperature. Keep mulch several inches away from the trunks and main stems.

Magnolia 'Susan' may experience leaf spots, anthracnose, cankers, dieback, or powdery mildew. Improve air circulation, water at the soil line, remove damaged tissue, and avoid unnecessary leaf wetting.

Possible pests include scale, thrips, snails, and weevils. Inspect plants regularly and use the least-disruptive control appropriate for the pest and severity of the infestation.

Plant Magnolia 'Susan' in spring or fall when temperatures are moderate and the soil is workable. Fall planting is often useful in many U.S. regions, but spring is preferable where severe winter cold arrives early.

Dig a hole about as deep as the root ball and two to three times as wide, then set the plant with the root flare at or slightly above soil level. Backfill with the native soil, water thoroughly, and mulch without covering the trunk.

Magnolia 'Susan' can be grown temporarily in a large container, but it is ultimately better suited to the ground because it develops a substantial root system. Use a deep, well-drained pot and expect to monitor watering closely.

Transplanting an established Magnolia 'Susan' is risky because magnolias have fleshy, easily damaged roots. Move only a relatively young plant if necessary, and preserve as much of the root ball as possible.

Magnolia 'Susan' is usually propagated clonally by softwood cuttings, grafting, or other nursery methods. Seed-grown plants may not reproduce the named cultivar consistently.

You can grow magnolia seedlings from seed, but they may differ from Magnolia 'Susan' because the cultivar is a hybrid. Seed propagation is therefore unsuitable when an identical replacement plant is required.

Magnolia 'Susan' can be propagated from softwood cuttings, but rooting is often difficult and success depends on timing, humidity, rooting medium, and hormone treatment. Nursery propagation is generally more reliable than casual home propagation.

Prune Magnolia 'Susan' immediately after flowering, before new flower buds develop for the following year. Limit pruning to removing dead, damaged, crossing, or poorly placed branches whenever possible.

You can control its shape and modestly reduce its size with selective pruning, but repeated hard pruning is not ideal. Choose a suitable planting location and remove no more than necessary each year.

Magnolia 'Susan' is generally considered low risk, and no serious toxicity is documented for this cultivar. Even so, prevent pets from consuming large quantities of plant material and contact a veterinarian if illness follows ingestion.

Magnolia 'Susan' usually blooms in mid-April to early May in much of the United States, depending on climate and spring temperatures. Its flowers generally open later than those of star and saucer magnolias.

The flowers are goblet-shaped, about 5 inches wide, and typically deep fuchsia, purple-red, or reddish-purple outside with somewhat paler interiors. The six tepals may be slightly twisted or inwardly rolled.

Magnolia 'Susan' flowers are generally slightly fragrant, although fragrance intensity can vary with weather and individual plants. The floral display is usually more noticeable for color and timing than for strong scent.

Magnolia 'Susan' may produce occasional, lighter summer flowers after its main spring display. Repeat blooming is sporadic and should not be expected every year.

Magnolia 'Susan' has better spring-frost avoidance than earlier-blooming magnolias because it flowers later. However, an unusually late freeze can still damage open flowers or developing buds.