A tree form Hydrangea Is a zone 3 and grows to 6’ – 8’ high and wide. Prefers a moist soil and adaptable to soil conditions once established. Plant in full sun to part shade. An excellent small tree for the landscape. Lime green flowers bloom in July and last all season long. Blooms turn pink as the flowers mature. 10 gallon container.
Height: 6 feet
Spread: 7 feet
Sunlight: 
Hardiness Zone: 4
This selection is grafted onto a standard to raise the flowers to eye level, features enormous, dense upright panicles of flower heads that start out a soft lime green, fading over the summer to white and finally brown in fall
Ornamental Features
Limelight Hydrangea (tree form) features bold conical lime green flowers with white overtones at the ends of the branches from mid summer to late fall. The flowers are excellent for cutting. It has green deciduous foliage. The pointy leaves do not develop any appreciable fall color.
Landscape Attributes
Limelight Hydrangea (tree form) is a deciduous tree, selected and trained to grow in a small tree-like form with the primary plant grafted high atop a standard. Its relatively coarse texture can be used to stand it apart from other landscape plants with finer foliage.
This is a high maintenance tree that will require regular care and upkeep, and is best pruned in late winter once the threat of extreme cold has passed. It has no significant negative characteristics.
Limelight Hydrangea (tree form) is recommended for the following landscape applications;
- Accent
- General Garden Use
- Container Planting
Planting & Growing
Limelight Hydrangea (tree form) will grow to be about 6 feet tall at maturity, with a spread of 7 feet. It tends to be a little leggy, with a typical clearance of 3 feet from the ground, and is suitable for planting under power lines. It grows at a medium rate, and under ideal conditions can be expected to live for 40 years or more.
This tree performs well in both full sun and full shade. It prefers to grow in average to moist conditions, and shouldn’t be allowed to dry out. It is not particular as to soil type or pH. It is highly tolerant of urban pollution and will even thrive in inner city environments. Consider applying a thick mulch around the root zone in winter to protect it in exposed locations or colder microclimates. This is a selected variety of a species not originally from North America.
Limelight Hydrangea (tree form) is a fine choice for the yard, but it is also a good selection for planting in outdoor pots and containers. With its upright habit of growth, it is best suited for use as a ‘thriller’ in the ‘spiller-thriller-filler’ container combination; plant it near the center of the pot, surrounded by smaller plants and those that spill over the edges. It is even sizeable enough that it can be grown alone in a suitable container. Note that when grown in a container, it may not perform exactly as indicated on the tag – this is to be expected. Also note that when growing plants in outdoor containers and baskets, they may require more frequent waterings than they would in the yard or garden.
How to Prune Limelight Hydrangea into a Tree
imelight hydrangea (Hydrangea paniculata ‘Limelight’) usually stays around six to eight feet tall, but it can put on two to three feet of growth per season and get as tall as fourteen feet. Left on their own, hydrangeas tend to grow as rangy, unkempt, multi-stemmed shrubs. But we can do better. We have pruning shears! We can turn this variety of hydrangea into a small tree. Here’s how to prune your limelight hydrangea into a tree.
Limelight hydrangea is often trained to a branch-headed standard. Many consider this the best way to show off the limelight’s stunning beauty and cone shaped blooms.
A branch-headed standard is a tree or shrub pruned and trained to have a rounded “mop” head of branches atop a clear stem. (This differs from a central-leader standard whose branches retain a more elongate and feather-like shape atop a clear stem.)
Making the Cut
Select the strongest and straightest upright stem to be the central leader or “trunk” of your hydrangea, then remove any other wannabes. If you’re starting with a good sized plant, you may already have a suitable central leader. If not, you may need to use a stake to keep the anointed stem growing straight up. Tie it to the stake every few inches.
The limelight hydrangea in its tree form
Since it has no competition, the chosen trunk-to-be will grow faster and stronger, and soon will be a genuine trunk. Constantly remove any other shoots that come up from the ground. Side branches that grow from the main stem can be shortened to a few leaves and left until the main stem reaches the desired height; these leaves will provide energy to the growing main stem. Eventually we will want this central leader to be clear of any side branches for around two to four feet – your decision. It may take a year or two.
Make your pruning cuts just above paired buds; these buds will become two new branches growing opposite each other. Cut back to strong paired buds that are directed sideways, rather than towards the center and outside. Make cuts at an angle, so the wound is not horizontal which could allow rain water to collect.
When the central leader is the desired height, cut the tip off to halt its growth. We want our limelight hydrangea to have a rounded crown atop a smooth, straight trunk – like a lollipop. Remove side branches on the lower two-thirds of the main stem as they appear.
At least once a year, shorten long branches growing on the upper third of the main stem by a third of their total length. Every time you make a cut, at least two more branches will develop below.
Other annual maintenance should include:
Cutting off old flowerheads still remaining from the previous season, this will encourage new flowering
Removing dead branches
Cutting out branches that are crossing or interlocking
Removing smaller internal and side shoots which tend to produce smaller flower heads than do the larger, outward growing branches. (If you want more – but not larger – blooms, leave more of the thinner, internal stems.)
A mature Hydrangea tree can be a focal point in the landscape. Pruning a limelight hydrangea into its form of the tree is not the easiest task. It can be done though! We here at Perfect Plants already went through the motions for you and have a Limelight Hydrangea Tree for sale for those who do not want to try out this gardening endeavor.
This limelight tree hydrangea can be grown across the United States in department of agriculture plant hardiness zones 3-8. Hydrangeas bloom on a single stem. Your yard will thank you after pruning this shrub into its tree form or just purchasing the already trained tree.