Clematis – ‘Diamond Ball’ – Clematis sp.
"Feet in the shade, head in the sun" is the old maxim for successfully growing clematis, so plant it where the vine gets sunshine but the roots stay cool. You can accomplish this with mulch, or by shading the root zone with a nearby shrub or perennial. 'Diamond Ball' clematis flowers on both old and new wood, so for pruning, cut it back to 18" (45 cm) tall in early spring. Provide a trellis or other structure for clematis to climb on at planting time.
Uses Notes specimen plant; borders; trellis
Maintenance Category Easy
Water Category Average
Blooms On New Wood, Old Wood
Heat Zones 9
Flower Form Border Plant, Container, Landscape, Specimen or Focal Point
pH B - pH 5.8 - 6.2
EC (2:1 Extraction Method) 0.6 - 0.9
Fertilization 100 - 150
Light Requirements High
Water Requirements Moderate to Moist
Rooting Out Temperature 62 - 66° Fahrenheit
Growing On Temperature 58 - 62° Fahrenheit
Holding Temperature 40 - 50° Fahrenheit
Planting and Timing Information
2 1/4" finishes to 1 gallon in 10-12 weeks, Quick Turn finishes to 2-3 gallon in 14-18 weeks.
Grow plants cool early in the season to prevent top growth from outpacing root development, which complicates maintenance later. Lower fertility also helps with this issue. Should be grown in larger, rather than smaller, pots, with a bamboo trellis or similar structure placed in the soil. Use a light, fast-draining growing media. Pinch/prune 2-3 times to encourage branching and minimize plants growing into each other. Plants benefit from manual training of vines onto support structure, which results is less maintenance and a more appealing plant at retail. Once flower buds have set, grow plants drier to prevent clematis wilt. Spray with thiophanate-methyl fungicide as a preventative. Top-dress with rice hulls or something similar to minimize weeds, algae, liverwort, etc., since leaf coverage of soil is minimal. Should be last plants to be moved outdoors. Potting a 2 ¼” liner directly to a 3 gallon can is not recommended. Additional notes on Happy Jack® Purple and 'Diamond Ball': One of the easiest varieties to ship in bud and bloom. Additional notes on 'Sweet Summer Love': Late bloom makes shipping flowering plants tricky. Being pot-bound seems to encourage blooming on this variety.