‘Ruby Slippers’ is a cultivated variety of the oakleaf hydrangea, which is native to southeastern North America and as such attracts pollinators. The variety is a hybrid between the oakleaf hydrangea ‘Snow Queen’ and ‘Pee Wee’. It was introduced in 2010 by the U.S. National Arboretum as a small, compact, mounding shrub that is especially suited for residential settings with limited space. If you have a small yard or patio and want a striking hydrangea that also has native heredity, ‘Ruby Slippers’ fits that bill. In addition to beautiful blooms and year round interest this small shrub attracts pollinators.
Light
In their native southern climate, oakleaf hydrangeas grow in the shade of tall trees, which protects them from the hot afternoon sun. So if you live in a warm climate, plant it where it gets shade during the hottest hours of the day. However, if the location is too shady, the fall colors are less intense. In cooler climates, it can grow in full sun.
Soil
While hydrangeas prefer evenly moist soil, the soil should have good drainage—hydrangeas dislike wet feet. Amend clay soil with organic matter to improve drainage. If in doubt whether your soil is acidic, measure its pH and acidify the soil around the planting area as needed with Holly Tone or a similar supplement.
Water
During the first season, until the hydrangea is established, water it regularly to keep the soil evenly moist. Once it’s established, it can tolerate drier soil. But depending on sun exposure , watering during dry periods may still be necessary. Mulching around the plant helps to retain soil moisture and keeps the shallow root system cool.
Temperature and Humidity
Outside its native habitat of the southeastern US, oakleaf hydrangea is hardy yet its flower buds are vulnerable to winter injury when temperatures drop below minus 10 degrees Fahrenheit, which will lead to reduced or no flowering. If you are located in zone 5, it is best to plant Ruby Slippers hydrangea in a protected spot shielded from chilling winds, snow, and ice. As a native of the American south, the plant is well adapted to humid conditions.
Fertilizer
When grown in soil amended with ample organic matter, hydrangea requires no regular fertilization, but it will benefit from a bloom-booster in the spring. If your soil is alkaline, a special fertilizer for acid-loving plants will have the added benefit to keep the soil pH in the target range.
Pruning
Ruby Slippers hydrangea is a slow grower, and there is not much pruning to be done other than removing dead branches. Make sure to prune after the plant has bloomed, as oakleaf hydrangeas bloom on last year’s growth and you risk removing flower buds if you prune in the spring before the bloom.
Propagating Ruby Slippers Hydrangeas
Like all hydrangeas, oakleaf hydrangeas have shallow roots that send out suckers. Propagating these is done similarly as you would any hydrangea, through root cuttings, except that the suckers already have some roots.
Potting and Repotting
Ruby Slippers can be grown in large containers. Plant the hydrangea in a container slightly larger than the one you bought it in to allow for some growth before it needs another repotting. As long as you provide it with a pot that is the right size and a good drainage hole, it should do just fine.
Common Pests and Diseases
Just like oakleaf hydrangea, the Ruby Slippers cultivar is relatively unbothered by pests and diseases. It has a slight susceptibility to leaf blight and powdery mildew, and it might attract aphids and spider mites.
