Bobo hydrangea is the trade name for a dwarf variety of the panicle hydrangea (Hydrangea paniculata 'Ilvobo'). While similar to other hydrangeas in every other way, including care needs, it grows only two to three feet high and slightly wider, making it an excellent foundation shrub or short hedge. It can also be used in mixed shrub borders where larger hydrangeas might be overwhelming.
Bobo blooms from early to late summer with flowers that form large panicles with a pyramidal shape—an identifying feature of all paniculata hydrangeas. The flowers are initially white but gradually turn pink, then deepen into purplish as fall approaches. Bobo is not one of those hydrangeas whose floral color is dependent on soil pH. If you want to manipulate the color of your hydrangeas, grow a variety of Hydrangea macrophylla.
Panicle hydrangeas are generally fast-growing shrubs, expanding as much as 25 inches per year. As a dwarf plant, Bobo is a bit slower-growing, but depending on the size of the nursery plant purchased, it likely will reach its full stature within two years. The standard planting time is spring after the soil temperatures have warmed.
Like all hydrangeas, the plant is toxic to pets.
|Common Name||Bobo hydrangea|
|Botanical name||Hydrangea paniculata 'Ilvobo'|
|Plant Type||Deciduous shrub|
|Mature Size||2–3 ft. tall, 3–4 ft. wide|
|Sun Exposure||Full, partial|
|Soil Type||Loamy, well-drained|
|Hardiness Zones||3–8 (USDA)|
|Native Area||Cultivar, no native range|
|Toxicity||Toxic to dogs and cats|
Bobo Hydrangea Care
Caring for a Bobo hydrangea is nearly identical to caring for any panicle hydrangea. It will do well if planted in somewhat acidic, rich, well-drained soil. If necessary, alkaline soil should be acidified before planting by blending in plenty of peat moss or some agricultural sulfur. This plant doesn't like extremely hot conditions, so in the southern part of its hardiness range, Bobo will do best in shadier locations.
At the end of the season, rake up and remove any fallen foliage that might harvest fungal spores to, prevent fungal diseases.
Bobo does best in a full sun location in most regions, but it is very tolerant of part shade. In warm southern climates, it will need some shade from the afternoon sun but does not tolerate deep shade.
Panicle hydrangeas prefer acidic soil (pH range between 5.8 and 6.2) that is rich and well-draining, similar to that in which azaleas thrive. Neutral or alkaline soils can be amended with sulfur or peat moss to lower the pH. Unlike other hydrangea species, you can't change flower color by altering the soil pH.
Bobo will thrive with about one inch of water per week, either through rainfall or irrigation.
Temperature and Humidity
Panicle hydrangeas adapt well to the climate conditions throughout zones 3 to 8. Bobo is less affected by winter burn than some other varieties. Very humid weather can make it susceptible to leaf spots and other fungal problems, but the problem is rarely serious.
In rich soil, this plant will not need any feeding. If soil is poor, a light application of fertilizer in spring is a good idea—use a fertilizer formulation designed to promote flowering, such as 15-30-15. For the amount to use, follow the product label instructions. Avoid overfeeding with nitrogen, as this can lead to lush leaf growth but few flowers.
Dwarf varieties of panicle hydrangea are not common, but there are several other cultivars of Hydrangea paniculata to consider:
- 'Little Lime': This 3- to 5-foot variety has blooms that open as pale green, then develop into a deep pink as fall approaches. It blooms from July into September.
- 'Little Quick Fire': This is another 3- to 5-foot plant. It blooms from July into September with white flowers that gradually turn pink with red highlights.
- 'Lavalamp Flare': This is another very compact plant, at 2 to 3 feet. It blooms in July and August with white flowers that turn pinkish-red.
Bobo does not require regular pruning, as it has a naturally dense and compact form. If you want to prune it for shape as a hedge shrub, do so in early spring or late winter before new growth has started. Simply prune the tips of the branches to form the shape desired. This plant blooms on current year wood, so pruning too late in the spring will compromise the flower production for that year.
Propagating Bobo Hydrangea
Bobo is a trademarked variety and its propagation, either by cuttings or from seed, is an infringement of intellectual property rights.
Potting and Repotting
Bobo is small and compact enough to be grown in a container. Transplant it from its plastic nursery pot to a terra-cotta pot, which works better for hydrangeas because it absorbs water and the soil remains cooler. The container should be one or two sizes larger than the current pot and have a wide, flat base to prevent the top-heavy hydrangea from toppling over. Make sure the pot has large drain holes. Add enough potting mix to fill the pot and gently press it down. Water it well until water runs out of the drain holes.
Like all container plants, potted hydrangea needs more frequent watering than plants in garden soil.
When planted in garden soil, Bobo does not need any winter protection although adding a layer of mulch around the base is always a good way of insulating the roots against the cold.
Potted hydrangeas need to be protected from winter chills. There is no need to bring the containers indoors but provide additional insulation around the container. Either place it in a larger pot or box and fill the space with mulch or sand or build a silo to winterize the plant. You can also wrap the sides of the container with bubble wrap or burlap.
Common Pests & Plant Diseases
Bobo hydrangeas can be susceptible to bud blight, bacterial wilt, leaf spot, rust, and powdery mildew. These are more likely to occur in warm, wet climates, or where air circulation is poor. Water at the base of the plant rather than overhead to reduce the chances of fungal infection. If necessary, a fungicide spray such as copper can be applied to prevent or treat fungal infections.
Aphids and mites can be occasional problems. Blasting the plant with water spray can often dislodge these pests. Or, they can be treated by spraying the plant with horticultural oil or pesticide.
How to Get Bobo Hydrangea to Bloom
To encourage Bobo hydrangea to bloom, use a fertilizer that is high in phosphorus and not high in nitrogen, which only encourages foliage growth. Make sure it gets the right amount of sunlight, either too much or too little sun can affect the bloom. Don't prune in the spring when you might accidentally remove new buds.
If you've taken all of these steps and your Bobo hydrangea still doesn't bloom, the flower buds might have been killed during a late spring frost, or one of the other reasons why a hydrangea doesn't bloom—it is not yet fully established.
Should Bobo hydrangeas be cut back in the fall?
You can remove dead wood in the fall but pruning is usually done in the late winter or very early spring. This makes more sense because then you can also remove any branches or twigs that have died over the winter. Because Bobo hydrangea blooms on new, current-year growth, dieback over the winter does not affect the bloom.
Do you deadhead Bobo hydrangeas?
It is not necessary unless the stems are bending and flopping over and you want to selectively deadhead a few spent flower heads to give the plant a neater appearance.
How far apart do you plant Bobo hydrangeas?
Space them four feet apart if you want them to stand out as individual plants. Or, for a dense hedge, space them 36 to 42 inches apart, measured from the center of the plant. Keep in mind though that poor air circulation can promote fungal infections, especially in humid conditions.
Hydrangea paniculata 'Ilvovo' BOBO. Missouri Botanical Garden