Hydrangeas are easy to grow and are unrivaled in bloom size, producing balloon-sized blooms in shades of pink, blue, purple and white (sometimes they all grow on the same shrub!). These large blooms are long-lasting when cut and used for a fresh floral arrangement, plus the blooms dry easily for use in dried floral arrangements. These beautiful and easy-to-grow perennial shrubs can certainly become one of the foundations of your garden. Follow these tips for successfully growing hydrangeas at home.
Hydrangea Types
Firstly, it is good to be introduced to the main hydrangea cultivars, although there are hundreds of varieties. Some of the popular types are:
- Mophead hydrangeas
- Lacecap hydrangeas
- Smooth hydrangeas
- Panicle hydrangeas
- Oakleaf hydrangeas
Mophead and Lacecap hydrangeas are both classified as “bigleaf” hydrangeas (Hydrangea macrophylla), and noted for their large flower head blooms that develop in spring. These are the most commonly grown of all the hydrangeas. The “Mopheads” are so called due to their roundish flower heads, while the “Lacecaps” are named after their flattish flower heads.
Smooth hydrangeas (Hydrangea arborescens) have even larger white blooms than other hydrangeas and can thrive in the rather cold climates of Zone 3 all the way to Zone 9. Panicle hydrangeas (Hydrangea paniculata), also known as Peegee hydrangeas, can grow as tall as a small tree while producing huge flower heads in the summer. They are also one of the most cold-hardy hydrangeas around and able to grow in Zones 3-7.
Oakleaf hydrangeas (Hydrangea quercifolia) has large dark green leaves (looking like oak tree leaves) that turn into shades of red, orange, and maroon in autumn and persist into winter. They develop cone-shaped flower heads, quite unlike the Mophead and Lacecap hydrangeas with their rounded or flat topped flower heads.
Growing Location
Hydrangeas are not picky about where they grow and can be planted in-ground or in a container. They will tolerate poor soil conditions and can live for decades if given plenty of water and provided the climate isn’t too harsh.
Select a growing location that receives morning sun and yet provides shade from the hot afternoon sun for your hydrangea. Try to avoid planting them directly underneath trees though; it can lead to competition for the same resources. Beside a wall/fence that is near a water source is probably best. These shrubs require a lot of water and choosing a growing location near a water source makes caring for the hydrangea easier for you.
Soil
While hydrangeas will adapt to most soil conditions, they thrive in rich, porous, moist soils. Add compost to soil before planting and mulch the shrub after planting. What is interesting about hydrangeas is their bloom color is affected by soil pH. Acidic soil with pH below 5.5 will produce blue flowers; soil with pH over 5.5 tend to result in pink flowers. Meanwhile, white flowers are not affected by the soil pH.
You can of course amend the soil pH by mulching the root base of the shrub with pine straw or by adding used coffee grounds around the shrub. There are also commercial solutions for amending the soil pH easily, which you can obtain online.
How and When to Plant
Hydrangeas are normally planted from cuttings. Plant hydrangeas either in spring or autumn, because they prefer milder temperatures. Dig a shallow hole so that the crown of the plant (where the base of the stems touches the soil) is level with the ground level and preferably the planting hole should be twice as wide (and about 2 feet wider than the root ball) as it is deep.
Place the shrub in the hole and fill it up half-way with soil. Add water to the soil, and allow it to drain. After water has drained, complete filling up the rest of the planting hole with soil. The plant should be level with, or slightly higher than the surrounding soil.
Watering and Feeding Schedule
Water is rapidly lost through the large leaves, and hydrangeas dehydrate easily in the summer heat. Water deeply twice a week during the summer; more often if the leaves show signs of wilting. Feed the shrub with your favorite balanced fertilizer about three times a year – in early spring, early summer, and once again in mid-summer. Add organic mulch to the base of the plant to keep the moisture and temperature level of the soil constant, while improving the soil nutrients and texture.
Pruning a Hydrangea
As a general rule of thumb, pruning should be done immediately after the shrub has finished blooming and flowers have faded. Hydrangeas set their buds for next year’s blooms soon after they are finished blooming, so the best time to prune is right after the present bloom which is usually in summer.
If you prune too late, you could end up removing the new blooms for next year as well. A few hydrangeas should be pruned in late winter though, before their active growth starts – these include panicle hydrangeas (Hydrangea paniculata), and snowball hydrangeas (Hydrangea arborescens). Remove dead or diseased stems or unwanted growth while removing the spent blooms. Use sharp pruning shears and make clean cuts.
Drying Hydrangeas
Harvested flowers can be dried, but don’t expect them to retain their colors while they were still on their mother plant. You should time your cutting appropriately; too early and the flowers will wilt, while too late and they can lose all their color. To retain the most color, let the flowers dry a little while on their shrub. Midway through the blooming, the flowers turn a little papery and that is when to cut the flower heads (along with a portion of their stem).
Snip off the leaves from the stem and place them in a vase with water about 1-2 inches deep, away from direct sunlight. Leave the flowers there to dry out slowly, while letting the water slowly evaporate. When the water has dried up, the flowers will have a papery texture and should retain most of their color for quite a while to come.