Cutting hydrangeas – timing and instructions

• Peasant hydrangea (Hydrangea macrophylla)
• Oakleaf Hydrangea (Hydrangea quercifolia)
• Climbing Hydrangea (Hydrangea petiolaris)
• Velvet Hydrangea (Hydrangea aspera)
• Teller-Hortensie (Hydrangea serrata)

Pruning category 2: this year’s planting of the flower buds

• Rispen-Hortensie (Hydrangea paniculata)
• Snowball hydrangea (Hydrangea arborescens)

The following statements always refer to the respective hydrangea species, while at the same time implying all associated varieties.

Correct time for cut category 1

If hydrangeas shed their leaves in autumn to prepare for the cold season, they have already created the buds for the next season. If you open a bud, you can already see small leaves and the new inflorescence. The great blossoms of summer past are now withered; are still stable at the end of the stem. Experienced hobby gardeners know the decorative effect of these parchment-like blossoms when they are covered in glittering frost and delicate snowflakes. Category 1 hydrangeas are therefore not cut until next spring.

Optimal time for cut category 2

Hydrangea species and their varieties in this group are cut back in late autumn. If you want to leave the withered flowers in the garden during the winter, you can also prune them in early spring. In this case, please remember not to wait too long, because these ornamental shrubs bud very early in the season. In the worst case, a delayed pruning causes a total failure of this year’s flowering.

Instructions for pattern category 1

Farmer’s hydrangea (Hydrangea macrophylla)
With a growth height of 200 cm, farmer’s hydrangea captivate with an impressive habit. The flowers are either umbel-like and flat or spherical in shape. Its flowering period begins at the end of June and lasts until September with good care. This species is also known under the names garden hydrangea, potted hydrangea and Japanese hydrangea.

• Cut off the old inflorescence just above the first young bud
• Do the same with frozen shoot tips
• Thin out the ornamental shrub altogether

Oak-leaf hydrangea (Hydrangea quercifolia)
The most striking feature of an oak-leaf hydrangea is the up to 30 cm long, cone-shaped inflorescence. This species owes its name to the large leaves, which actually look very similar to oak leaves and also turn reddish in autumn. With its powerful habit and a height and width of up to 3 meters, annual pruning is all the more important the smaller the garden. If you miss it, sooner or later the oak leaf hydrangea will grow over your head. If you are forced to cut off too long branches below the newly planted buds, the hope of flowering this year is gone.

Climbing hydrangea (Hydrangea petiolaris)
As a self-climber, the climbing hydrangea is popular in facade greening. With its powerful adhesive roots, it climbs up to 15 meters in height and reaches widths of 5 meters. If it gets to fence posts, trees or flagpoles as ground cover, it climbs them as well. Umbrella-shaped, white umbels of flowers appear above the dense, green foliage at the end of May and only wither in late summer. In view of the very slow growth, hobby gardeners do not consider pruning in the first few years. However, the first pruning should not be postponed for too long. Since the climbing hydrangea belongs to cutting category 1, cutting too generously will always be at the expense of the flower.

• In the spring, cut off dried and frozen tendrils at the base
• Keep an eye on the balance of the climbing plant with every pruning
• Cut back ground covers before reaching obstacles at the latest

Velvet hydrangea (Hydrangea aspera)
Its velvety leaves and delicately hairy shoots were the inspiration for the name. Distinctive, bicolored flowers up to 25cm in diameter appear with a ring of white pseudoflorets surrounding purple, blue or pink fertile flowers. Depending on the variety, this type of hydrangea thrives between 100 cm and 400 cm, so it is often cultivated in a bucket. Thanks to the extra large leaves, it is sometimes referred to as a giant leaf hydrangea, more rarely as a fur hydrangea.

• Leave the flowers on the bush as winter decorations
• Wait until severe frost is no longer to be expected before pruning
• Prune frozen shoots down to the first healthy new bud

Plate hydrangea (Hydrangea serrata)
It enchants with an unusually filigree appearance. Its flat, two-tone flowers are smaller in diameter, but they catch the eye with their particularly large pseudo-flowers. With a maximum growth height of 100 cm, it is recommended as the ideal hydrangea for the small garden. The plate hydrangea is also known as the mountain hydrangea.

• In spring, remove the faded inflorescence
• Thoroughly thin out the inside of the bush

Instructions for pattern category 2

Panicle hydrangea (Hydrangea paniculata)
The panicle hydrangea is not only used as an ornament as a classic shrub, but is often cultivated as a small tree. With a growth height of 2 meters and higher, both variants are quite feasible. The lilac-shaped flowers appear late in summer and linger until the first frost. Since this type of hydrangea does not develop its buds until next spring, the hobby gardener is free to choose whether to cut the withered flowers in autumn or in late winter.

• Shorten shoots that are too long at your own discretion
• At least 1 pair of eyes should remain in the branch
• Prune regularly when training to become a tree

Snowball hydrangea (Hydrangea arborescens)
It has become the secret star among the hydrangea species. Nobody can escape the spectacular flower balls in brilliant white. As a member of Pruning Category 2, flowers do not form until later in the year. In mild weather, they can still be admired well into November.

• Towards the end of winter, shorten the shoots to 2 pairs of eyes
• Two new shoots will form from each of these old branches
• Thinning out only required from the 5th or 6th year

The result of this pruning technique is a hydrangea that grows denser and more compact from year to year. If the first thinning was only necessary after a few years, the rhythm shortens parallel to the compaction of the crown. So that the ornamental shrub does not bare from the inside, not only remove dead wood, but also cut off weak branches that are growing out of shape.

exceptions

The hydrangeas ‘Endless Summer’, ‘The Bride’, ‘Twist’n Shout’ and ‘Bella Anna’ have a special status. From a botanical point of view, they belong to the farmer’s hydrangeas – and thus to cut category 1; the pruning, on the other hand, is carried out taking special aspects into account. The two varieties easily tolerate a strong pruning in the spring. They sprout again in the same year, because they bloom on both the old and the new wood.

• Thin out carefully in autumn or winter
• Cut back to desired length in spring
• The older the hydrangea, the harder it can be pruned
• The more restrained the cut, the earlier the flower will appear

If a particularly harsh winter has destroyed all the buds that have already formed, there is no reason to worry with these special hydrangeas. In the spring, cut out any frozen parts of the plant and be patient. Fresh buds form on the new shoots in spring, which bloom in the same year.

Rules for pruning hydrangeas

Regardless of the cut category, it is advisable to follow a few fundamental rules:

• Only use freshly sharpened, disinfected cutting tools
• Put on protective clothing, including gloves and eye protection
• Cut hydrangeas in dry, windless, frost-free weather

Remember that you can’t put a ladder on even tall hydrangeas. A stepladder should therefore be within reach. Alternatively, you can use telescopic scissors to reach shoots that are further away.
These factors apply to each pruning measure:

• Position the scissors at a slight angle 3-5 mm above a bud
• After the complete removal of a branch, no stub should be visible
• Always cut branches that cross or point inwards

It is important to concentrate on each individual cut and to keep an eye on the habit of the bush as a whole. Experienced hobby gardeners step back from time to time during the work and look at the result so far.

taper cut

A wide variety of circumstances can make a radical pruning of hydrangeas seem unavoidable. If there is no shape and maintenance cut for several years, the ornamental shrub will eventually get out of shape. Likewise, in the case of a stubborn pest infestation or a far-reaching fungal infection, a rejuvenation cut is the last resort. Ideally, it takes place in late winter in order to use the coming shoots to rebuild the ornamental tree.

• Cut off 3 to 4 strong main shoots to 10-20 cm above the ground
• At least one pair of eyes is below the cut
• Cut all other shoots completely at the base

The dormant nodes are activated to sprout in spring. For the next 12 months, let the hydrangea do its thing. Next spring, move on to the second phase of rejuvenation:

• Thin out the hydrangea, except for 3 side shoots per main shoot
• These branches, in turn, shorten by about a third
• Tear off steeply upright water shooters at the base

In the 2 to 3 years that follow, the natural growth form develops without any pruning. The hydrangea sprout willingly, as in its best times. The first bloom after the radical pruning accordingly signals the beginning of the pruning rhythm in the sequence explained.

Conclusion
Don’t get confused when it comes to pruning hydrangeas. It’s easier than you might think. Once it is clear which cut category the ornamental shrub is to be assigned to, there is clarity about the right time. In the next step, clarify the question of which hydrangea species the wood belongs to in order to familiarize yourself with the specific characteristics. In this way it is ensured that the pruning has a beneficial effect on the flowering and does not prevent it. The exceptional hydrangeas of the breeding line ‘Endless Summer’ and ‘The Bride’ are a little out of the ordinary when it comes to the requirements for shape and maintenance pruning. Of course, they do not present insurmountable hurdles. On the contrary, such modern hydrangeas offer even more flexibility when cutting.