Mary Nell holly

Sun

Full sun to partial shade; growth is denser and berry production usually better in sun.

Water

Moderate; keep the root zone evenly moist while establishing, then water during prolonged dry spells.

Soil

Moist but well-drained, acidic soil enriched with organic matter; avoid waterlogged ground and strongly alkaline soil.

Height

15-25 ft (4.6-7.6 m)

Spread

10-15 ft (3-4.6 m)

Flowers

Small, creamy-white flowers in spring; inconspicuous among the leaves.

Foliage

Large, glossy, dark green leaves with numerous sharp marginal spines; dense evergreen cover.

Growth

Moderate.

Care needed

Low

• Pollinators
• Heat tolerant
• Wildlife
• Low allergen

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Easy

Toughness

Very tough

Pick your zone, country, light and whether you have pets.

1. Planting day

   2.4 ft (0.73 m)

2. After 1 year

   6 ft (1.8 m)

3. After 2 years

   9 ft (2.9 m)

4. After 3 years

   13 ft (4 m)

5. After 5 years

   20 ft (6.1 m)

   full size

About 5 years to full size.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Toxic

Growth rate

Moderate

• Water deeply during the first two growing seasons whenever the root zone begins to dry.
• Apply 2-3 in (5-8 cm) of organic mulch, keeping it away from the stems.
• Feed lightly in spring only if growth is weak or a soil test indicates a need.
• Provide a compatible male holly with overlapping spring bloom if you want berries; another female plant will not pollinate it.
• Allow for its mature width rather than relying on frequent shearing to keep it small.

Pruning. Prune in late winter or early spring before new growth, removing dead, crossing or misplaced branches and shortening shoots selectively. Avoid repeated shearing if you want berries, since it removes flowering and fruiting growth.

Late winter

Remove dead or damaged branches and make any necessary shaping cuts.

Spring

Plant when the soil is workable, water thoroughly and mulch the root zone.

Spring

Check that a compatible male holly flowers at the same time if berry production is important.

Summer

Water young plants deeply during dry weather and check leaves for scale insects.

Autumn

Check soil moisture before winter and replenish mulch without piling it against stems.

Winter

Enjoy the berries and leave fruit for birds; gently lift heavy snow from branches if needed.

• Plant as a tall evergreen boundary screen, leaving enough space for the shrubs to develop their natural width.
• Use a single specimen as a dark green backdrop to hydrangeas and flowering perennials.
• Repeat along a broad drive or property edge for a consistent pyramidal outline.
• Combine with witch hazels, dogwoods and early bulbs for a winter-interest planting.

Garden styles it suits: Traditional, Southern, Formal, Grand estate, Woodland and Winter interest.

Plant it with: Oakleaf hydrangea, Camellia, Witch hazel, Japanese pieris, Hellebore and Daffodil.

Wildlife: Flowers attract bees and other pollinating insects. Birds eat the berries, often later in winter, and the dense branches provide shelter and nesting cover.

• Yellow leaves with green veins: alkaline soil can make iron unavailable; test the soil and address pH rather than repeatedly adding general fertiliser.
• Scale insects and sooty mould: inspect stems and leaf undersides; use a labelled horticultural oil at the appropriate stage and avoid spraying during excessive heat.
• Root rot or dieback in wet ground: improve drainage and reduce watering; badly affected plants may need replacing in a better-drained position.
• Few or no berries: check for a compatible male holly flowering nearby, increase sunlight where practical and avoid pruning away flowering growth.

Treat the berries and leaves as toxic to people, cats, dogs and horses. Eating them can cause vomiting, diarrhoea and abdominal discomfort; berries are the main ingestion risk. Keep children and pets from eating fallen fruit, and seek medical or veterinary advice after ingestion.

• Nellie R. Stevens holly (Ilex 'Nellie R. Stevens')

  Has similarly glossy leaves and a pyramidal habit, but its leaves usually have fewer, more widely spaced marginal spines than Mary Nell.

• Burford holly (Ilex cornuta 'Burfordii')

  Its broad, glossy leaves usually have a single prominent spine at the tip, rather than the many marginal spines of Mary Nell.

Propagation. Root semi-ripe cuttings in summer, usually with rooting hormone and controlled humidity. Seed does not reproduce the named cultivar and may take a long time to germinate.

Accepted botanical name

Ilex

Sources: GBIF (CC BY 4.0). The care and design notes are LandscapeGPT's own.