Minnesota Hydrangea Winterization Tips?

In Minnesota, bigleaf or oakleaf hydrangeas require winter care to ensure their flower buds survive until spring. This includes preparing soil, planting times, water requirements, sunlight needs, fertilization, pest and disease control, pruning techniques, and winter care. To prepare hydrangeas for the Minnesota winter, trim back stems in late winter, early spring, or just above a big bud called a heading cut.

To protect mophead and lacecap hydrangeas during winter, mound shredded leaves or bark mulch around the base of the plant to about 12 inches or so. Place the mulch mound in late fall after the ground freezes, and uncover plants in spring when temperatures begin to stay above freezing. Apply a layer of chunky mulch around the base of the plant, with decorative mulch being recommended.

To winterize hydrangeas, lay down a thick layer of mulch or straw over the root area at the base of the plants to help protect them from the long, cold winter. Prune back stems to just above a fat bud (heading cut) in fall, late winter, or spring. These plants have conical-shaped flower heads that provide winter interest.

Keep the soil moist until the ground freezes, then cut the shrubs back to around 8-12 inches. Winterize with leaves, straw, or other similar material, and cover the full plant with a garbage bag full of leaves and crown for extremely cold nights.

Should hydrangeas be cut all the way back?

To prune hydrangeas, start in early spring by cutting back last year’s growth to a healthy framework between 30cm and 60cm high. Prune to just above a pair of healthy buds on each stem, and cut back to the lowest healthy buds for big flowers or less hard for a natural look or taller plant. Climbing hydrangeas like Hydrangea anomola subsp. petiolaris and Hydrangea seemannii should not be pruned until after flowering.

What does a hydrangea look like in winter?

The most probable cause of the death and deterioration of hydrangeas’ foliage and buds during the winter season is the loss of the majority of their blooms, which frequently become desiccated and discoloured, coupled with the adverse effects of low temperatures.

How do you save hydrangeas after frost?

In order to facilitate the recuperation of the hydrangea from the effects of frost, it is recommended to await the advent of warmer weather and to prune the plant back to the next healthy bud or set of leaves. It is possible for old-wood bloomers to continue blooming at the base of the plant, while new-wood bloomers can be pruned to a height of a few inches above the ground. To facilitate the recuperation of the hydrangea, it is recommended to apply a layer of organic mulch in the spring and to irrigate with an appropriate organic fertilizer.

Where do you keep hydrangea cuttings over winter?

To take hydrangea cuttings, use secateurs to collect material from stems and a knife to trim each cutting. Due to their woody nature, they cannot be propagated in water, so they should be placed in a pot of gritty compost. Keep them in a propagator to retain moisture until roots develop, usually after six weeks. The cuttings will rooted when new leaves develop and resistance from roots in the soil is felt. Transplant the rooted cuttings into individual pots for growth, overwinter them in a cold frame, or overwinter them as is and transplant them the following spring.

The cuttings should be well-rooted and ready to plant into larger pots or gardens. The required tools include secateurs, sharp knife, 7cm pots, gritty, well-drained compost, and healthy, non-flowering shoots 10-15cm long.

What is the best month to prune hydrangeas?

Hydrangeas are typically pruned in late winter or early spring, with climbing hydrangeas being pruned after flowering in summer. Hydrangeas bloom from mid- to late summer, while mophead and lacecap hydrangeas bloom satisfactorily with little attention. Annual pruning encourages new growth and better flowering display. Other species, including climbing hydrangeas, benefit from a trim. Timing is usually late winter/early spring, but sometimes late summer. Pruning hydrangeas can be easy to moderate.

Should hydrangeas be cut back for winter?

Hydrangea paniculata, also known as panicle hydrangea, is a plant with conical-shaped flower heads that can be pruned back to just above a fat bud in fall, late winter, or spring. These plants produce buds in late summer to early fall, which will form next year’s flowers. To maintain winter interest in your landscape, it is recommended to wait until late winter or spring. Popular panicle hydrangeas include Quick Fire®, Limelight, and First Editions® Berry White®.

Should I cover hydrangeas for freeze?

Hydrangeas need protection depending on the winter temperature drop. If the air temperature doesn’t drop below 0 degrees (zone 7) there is no need for winter protection. In colder climates, wrap or cover marginally hardy hydrangeas, especially those that bloom on old wood, like mop head/big leaf hydrangeas. Newer varieties bloom on both new and old wood. Hardier hydrangeas like paniculata and arborescens don’t need extra winter protection, but extreme cold can cause die-back of their branches.

If a colder than normal winter is predicted, consider covering plants with burlap or a mulch mountain. There’s still time to plant hydrangeas, as they can grow in Zone 4 and warmer zones (5 to 9) and fall is the best time for planting. Follow the steps above, especially watering and mulching.

What happens if I forget to prune my hydrangea?

If you forget to prune your hydrangeas for a year, they may grow too big, tangled, or have smaller, less showy flowers. To restore their beautiful shape, you can use proper pruning techniques, such as using sharp secateurs. Felco secateurs are a good choice, and even good secateurs can become blunt after a season, so sharpening them with a sharpening stone can help maintain their strength. Remember to use a good pair of secateurs for optimal results.

How do you preserve hydrangeas for the winter?

Hydrangeas are a beautiful and easy-to-preserve flower that can last up to a year. To dry them, hang them upside down in a cool, dry location, allow them to dry naturally on the stem until the petals feel papery, or use a mixture of water and glycerin. The ideal time to cut hydrangea blooms to dry is towards the end of their growing season (August through October), when the larger petals are starting to change color and develop a papery feel, and the tiny flowers are just beginning to open. This method helps maintain the flowers’ shape and color, ensuring their beauty is preserved long after they bloom.

What is the freezing point for hydrangeas?

Bigleaf hydrangea, oakleaf hydrangea, and mountain hydrangea are shrubs that can withstand harsh winter temperatures down to -15°F, but their dormant flower buds may be compromised. To protect them from severe winter damage, add a layer of mulch at the base of the hydrangea during late fall or after the first freeze. Wrap or cover them if temperatures dip below 0°F, minimizing the risk of damage. If growing in containers, bring them inside after the flowering season when temperatures drop below 45°F degrees.

Place them in a cool, unheated, dark, and dry place like a garage, basement, or mudroom. As temperatures rise, slowly acclimate them to warmer temperatures by placing them indoors in direct sunlight during the day, called hardening off. Some cultivars are created to be exceptionally hardy in areas with brutal winters, and some cultivars may be hardy in areas with harsh winters.

How do you overwinter hydrangeas?

In cold winter regions, it is recommended to keep potted Hydrangeas indoors in a cold greenhouse, protected against the winter sun. Overwintering in the dark is possible, but temperatures should not exceed 41 degrees Fahrenheit. A bright, warm hibernation is also possible, but not optimal due to scale insect attacks and inhibited flower buds formation. Pruning frozen or dead flower shoots should be done in spring after heavy frosts are over. Older Hydrangeas planted in semi-shade on humus-rich soil usually don’t need winter protection, as long as they have a species-appropriate location.

In continental climates, mulching shrubs in fall with a thick layer of leaves covered with pine twigs and temporarily covering crowns with winter fleece is recommended. Older varieties of Mophead Hydrangeas and Tea of Heaven do not rebloom, causing flowers to fail for a year after severe frost damage. Winter protection is generally recommended for newly planted Hydrangeas that have not yet experienced outdoor winters.