Endless Summer® Hydrangea

Endless Summer® Hydrangea grows in USDA zones 4–9 in full to part sun — in hot-summer regions it appreciates morning sun with afternoon shade. It performs best in rich, moist, well-draining soil, and the soil's pH is what determines whether your blooms come in blue or pink.

Planting

1. Choose a site with morning sun and some afternoon shade, sheltered from harsh, drying wind.
2. Work compost into rich, well-draining soil; for blue blooms keep the soil acidic, and for pink blooms aim for neutral to slightly alkaline.
3. Dig the planting hole twice as wide as the root ball and no deeper than the root ball is tall.
4. Set the plant so the crown and root flare sit level with the surrounding soil, then backfill and water in thoroughly to settle out air pockets.
5. Spread 2–3 inches of mulch over the root zone to hold moisture and even out soil temperature, keeping the mulch pulled back off the stems.

Care & maintenance

• Water. Keep the soil consistently moist, especially the first season and during summer heat; bigleaf hydrangeas wilt quickly when dry. Deep, regular watering beats occasional light sprinkles.
• Feed. Apply a balanced or bloom-supporting shrub fertilizer in early spring as growth begins; a light second feeding in early summer supports continued reblooming. Avoid heavy late-season feeding.
• Light. Full morning sun with afternoon shade is ideal; too much hot, direct sun causes wilting and scorched leaves, while too much shade reduces flowering.
• Prune. Because this reblooming type flowers on both old and new wood, heavy pruning is not needed — simply remove dead or weak stems and deadhead spent flowers. If you want to shape it, prune lightly right after the first flush so you do not sacrifice developing buds.
• Mulch & winter care. Maintain a steady mulch layer year-round. In the colder end of its range, a deeper winter mulch protects the old-wood buds, helping the earliest blooms.
• Pests & disease. Watch for powdery mildew and leaf spot in crowded, humid conditions — good airflow helps. Aphids and spider mites may appear; treat as needed. Wilting is usually a watering issue, not a disease.
• Bloom color tip. Color follows soil pH: add soil sulfur or aluminum sulfate to acidify for blue, or add garden lime to raise pH for pink. Expect the shift to take a season or two.

When does it bloom and how long?

Endless Summer® blooms from spring through fall. As a reblooming bigleaf hydrangea, it sets flowers on both old and new wood, so after the first early flush it keeps pushing new mopheads through the warm months instead of finishing in a single burst.

Why isn't my hydrangea blooming?

The most common causes are pruning at the wrong time (cutting it back hard in fall or late winter removes developing buds), too much shade, a late frost that damaged old-wood buds, or over-feeding with high-nitrogen fertilizer that pushes leaves at the expense of flowers. Because this variety also blooms on new wood, it usually recovers and flowers later in the season even after a rough winter.

How do I get blue versus pink blooms?

Bloom color is controlled by soil pH. Acidic soil produces blue flowers; neutral to alkaline soil produces pink. To shift toward blue, acidify the soil with soil sulfur or aluminum sulfate; to shift toward pink, add garden lime to raise the pH. The change is gradual and usually takes a season or two to fully show.

When and how should I prune it?

This reblooming type needs very little pruning. Remove dead or damaged stems and deadhead spent blooms to keep it tidy. If you want to shape the plant, do it right after the first flush of flowers rather than in fall or late winter, so you avoid cutting off the buds it has already set for next spring.

Does it grow in sun or shade?

It does best in full to part sun, and in most gardens that means morning sun with afternoon shade. Too much hot, direct afternoon sun causes wilting and leaf scorch, while deep shade reduces flowering. A spot on the north or east side of the house is often ideal.

Can I grow it in a container or as a hedge?

Yes to both. Its compact 4-by-4-foot habit suits a large container on a shaded patio, where you can also fine-tune the soil pH for the bloom color you want. Planted in a row about 3 to 4 feet apart, several plants form a soft, informal flowering hedge or a continuous foundation planting.