The parents of this lovely Lacecap variety were found growing on the wooded slope of a Korean mountain, which explains its exceptional hardiness. It produces delicate clusters of light blue flowers that last for several weeks in early to midsummer (July here in Connecticut), turning a stunning deep crimson as they age. Fall foliage is an attractive shade of burgundy. Excellent in a shady border with Ferns and Astilbes. 'Blue Billow' is a reliable bloomer through Zone 6, and adventurous gardeners in Zone 5, where flowering occurs 3 or 4 years out of 5 may also wish to give it a try. It also performs well at our nursery in full sun. Blooms on old wood.
Hydrangea is a valuable genus of some 100 species of shrubs and vines grown for their large and very showy flower heads. Hydrangeas are at their best in summer and fall—a quiet time for most woody plants—and are worth having for that reason alone.
For more information on Hydrangea care, click on Growing Guide.
HOW PLANTS ARE SHIPPED
The size of the plants we ship has been selected to reduce the shock of transplanting. For some, this means a large, bareroot crown. Others cannot travel bareroot or transplant best if grown in containers. We ship these perennials and annuals in 1 pint pots, except as noted. We must point out that many perennials will not bloom the first year after planting, but will the following year, amply rewarding your patience. We ship bulbs as dormant, bare bulbs, sometimes with some wood shavings or moss. Shrubs, Roses, vines, and other woody plants may be shipped bareroot or in pots. The size of the pot is noted in the quick facts for each item.
WHEN WE SHIP
We ship our bulbs and plants at the right time for planting in your area, except as noted, with orders dispatched on a first-come, first-served basis by climate zone. Estimated dates for shipping are indicated in the Shipping Details box for each item. Please refer to the Shipping Details box to determine the earliest shipping time. Unless you specify otherwise, fertilizers, tools, and other non-plant items are shipped with your plants or bulbs. Please supply a street address for delivery. Kindly contact us with two weeks notice, if you'll be away at expected time of delivery.
We guarantee to ship plants that are in prime condition for growing. If your order is damaged or fails to meet your expectations, we will cheerfully replace or refund it. Please contact our Customer Service Department at 1-800-503-9624 or email us at [email protected]. Please include your order number or customer number when contacting us.
Average Customer Rating: (19 Reviews) Write a Review
Rachel from Philadelphia PA
Planted in a shady corner, worried for the first year, but this year it is great! It is growing slowly but surely in a very tough area where it gets little sun, lots of pine needles, and is crowded by a huge fern. Never needs water or pruning, at least so far. The only hard part was waiting for it to get going.
CandyK from Stuart Virginia
I bought my first Blue Billow when I lived in Connecticut and they were my first WFF purchase when I moved to Virgina 5 years ago. Here in Zone 6-1/2 they bloom every year. Mine are in a shady foundation/front of the porch setting surrounded by Astilbe and put on a stunning display from spring until late fall.
lazy gardener from Boston MA
This is a great plant. I didn't need to baby it too much the first year, and it just survived a terribly dry summer (it's 3 years old now and well established). The flowers are so unusual and last a long time. One of my neighbors visits it every day to enjoy the show!
Virginia Gardner from Burke, VA
Blue Billow is a great hydrangea for my very shady problem area next to the driveway. It was slow and steady last season and is blooming for the first time this year. WFF has always sent me very healthy plants and great specimens. This is a beautiful hydrangea.
Garden Lady from New Brighton, PA
I have had Blue Billow in my shade garden for about 8 years and it has never disappointed me. Each year the blooms are lovely and prolific. I'm going to add another this year to a different shady area in my garden!
Latin Name Pronunciation: hye-dran'jee-uh
Growing H. serrata
Light/Watering: Most varieties thrive in full sun in the North, but in the South require afternoon shade. Moist soils that do not dry out are best; do not plant in hot, dry, exposed sites. Mulch to conserve moisture and buffer soil temperatures.
Fertilizer/Soil and pH: In some varieties, flower color is determined by the pH of the soil; at low pH (acid soils) flowers will be blue and at higher pH, flowers will be pink. Generally, a pH below 5.0 results in deep, vivid blues and as the pH rises the flowers range from blue to lavender to mauve to a vivid deep pink at pH 7.0 (neutral). The pH determines the availability of aluminum in the soil; this element is more readily available in acid soils, and this availability results in the blue flower color. Since phosphorus ties up aluminum in soils, using a fertilizer low in this nutrient will aid in attaining blue flowers. If pink flowers are desired and your soil is acid, simply add lime to raise the pH and use a balanced fertilizer. Aluminum sulfate will lower pH if blue flowers are desired.
How to test your soil?
We recommend that you visit your local Cooperative Extension Service to find out about soil testing in your area. Follow this link for a directory of institutions involved in the Cooperative Extension program.
Pests/Diseases: None serious. Occasionally powdery mildew will infect the foliage, especially in humid areas with poor air circulation. Treat with an appropriate fungicide if the problem is serious, and be sure to rake up and destroy all fallen foliage in the autumn.
Pruning: Little pruning is needed, but if shrubs grow too large, cut back stems by about one-third by the end of August. In spring, only prune out dead wood. Most Hydrangea serrata varieties bloom on old wood. H. s. Tuff Stuff™ is a variety that blooms on both old and new wood. If no fall pruning was done, stems can be cut back by one-third in spring if necessary—but this will sacrifice the bloom on the old wood and shrubs will not flower until late summer.
Transplanting: Young plants may be transplanted when dormant in early spring; larger tree-form varieties are difficult to move once established, but it can be done. Prune top growth after transplanting to reduce water loss.
End of Season Care: Rake up and destroy any fallen foliage that was infected by powdery mildew or other fungi.
Calendar of Care
Early Spring: Prune out any dead wood from all varieties. Check soil pH and adjust up or down if needed for desired flower color. Feed plants with a fertilizer high in phosphorus (such as 15-30-15) to encourage blooms. Complete any transplanting before leaves unfurl.
Mid-Spring: Mulch plants after soil has warmed to conserve moisture and buffer soil temperatures. Watch for powdery mildew and treat as needed.
Summer: As soon as blooms fade, remove old flowering stems. If needed, prune as indicated above by the end of August.
Fall: Remove and destroy any fallen foliage that was infected by powdery mildew. If not pruned in spring, plants can be shortened, or pruned back to the ground.
For more information on growing Hydrangeas, click here.