Transform your ordinary hydrangea bush into a stunning tree-form specimen that will become the centerpiece of your garden. Growing hydrangeas as trees, also known as “standards,” creates dramatic focal points with elegant single trunks topped by magnificent blooming crowns. This comprehensive guide will teach you everything you need to know about selecting, training, and maintaining hydrangea trees for years of spectacular garden performance.
Understanding Hydrangea Tree Forms vs. Bush Forms
The difference between a hydrangea bush and tree lies entirely in training and pruning techniques, not in plant genetics. Any hydrangea variety can potentially be trained into tree form, though some respond better than others to this treatment. Tree-form hydrangeas feature a single, sturdy trunk with all foliage and flowers concentrated in an upper canopy, creating a more formal, architectural appearance.
Tree-form hydrangeas offer several advantages over traditional bush forms. They provide better air circulation around the base, making underplanting easier and reducing disease pressure. The elevated flower heads create better visual impact and allow you to appreciate the blooms at eye level. Additionally, the space beneath tree-form hydrangeas can accommodate shade-loving plants, maximizing garden real estate.
The transformation from bush to tree typically takes 2-3 years of consistent training, depending on the variety and starting plant size. Patience and regular maintenance during this period are essential for success.
Best Hydrangea Varieties for Tree Training
Not all hydrangea species respond equally well to tree training. Hydrangea paniculata varieties perform exceptionally well as trees due to their naturally upright growth habit and strong wood structure. Popular cultivars include ‘Limelight,’ ‘Little Lime,’ ‘Pinky Winky,’ and ‘Vanilla Strawberry.’
Hydrangea arborescens varieties like ‘Annabelle’ and ‘Incrediball’ can be trained as trees but require more support due to their softer stems and heavy flower heads. These varieties benefit from strategic pruning to reduce flower size and weight.
Hydrangea macrophylla (bigleaf hydrangeas) present the greatest challenge for tree training due to their naturally spreading habit and tendency to produce multiple stems from the base. However, with persistent training, varieties like ‘Endless Summer’ and ‘Nikko Blue’ can achieve tree form.
Hydrangea quercifolia (oakleaf hydrangea) naturally develops multiple trunks but can be trained to a single leader with early intervention. The exfoliating bark adds winter interest to tree-form specimens.
Choose varieties known for strong stems and moderate flower sizes to ensure your tree can support its crown without staking indefinitely.
Starting with Young Plants vs. Mature Specimens
Beginning with young, unbranched plants provides the best opportunity for successful tree training. One-year-old rooted cuttings or small nursery plants adapt most readily to training, as their growth habits haven’t become established.
When selecting young plants, look for specimens with a single, straight central stem. Avoid plants that have already developed multiple leaders or extensive branching near the base, as these require more corrective pruning.
For mature hydrangeas, tree training remains possible but requires more aggressive intervention. You’ll need to select the strongest, straightest stem as your future trunk and remove all competing growth. This process may set back flowering for a season or two while the plant redirects energy into the chosen leader.
Consider the mature size of your chosen variety when planning. Compact varieties like ‘Little Lime’ create charming small trees perfect for containers or small gardens, while larger varieties like ‘Limelight’ can reach 8-10 feet as trees.
Initial Selection and Preparation
Choose a healthy plant with vigorous growth and no signs of disease or pest damage. The ideal candidate has a straight central stem with evenly spaced side branches that can be gradually removed over time.
Plant your hydrangea in a location with morning sun and afternoon shade, though this varies by variety. Ensure adequate spacing for the mature tree size – typically 6-8 feet from other plants or structures for most varieties.
Prepare the planting site with well-draining, organic-rich soil. Hydrangeas prefer slightly acidic to neutral pH (6.0-7.0) and consistent moisture without waterlogging. Amend heavy clay soils with compost and coarse sand to improve drainage.
Install a sturdy stake at planting time, positioned on the prevailing wind side. Use a stake that extends to about two-thirds the height of your desired final trunk height. This support will be essential during the first few years of training.
Step-by-Step Tree Training Process
Click on “Next” to continue reading.
