Today s Topics. Success with Hydrangeas. Duxbury Hydrangea Festival Duxbury Senior Center, August 1, Weather effects

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1 Duxbury Hydrangea Festival Duxbury Senior Center, August 1, 2017 Success with Hydrangeas Mal Condon Curator of Hydrangeas, Heritage Museums and Gardens President, The Cape Cod Hydrangea Society Weather effects Today s Topics Hydrangea species review Seasonal pruning best practices Intermission Container growing - a guaranteed approach to reliable summer blooming 2. Plant Hardiness Narrow Zone 6b along the Coast with colder 6a Inland, Milder 7a & 7b Winters not uncommon Boston to The Cape 4. Cold Hardiness Boston to the Cape, Islands & SE Mass The Not Always Winters of 2014, 2015, 2016, & 2015: much Colder than the previous 8 years; several Below Zero Days moved Us to Zone : very Snowy (but good insulator) and flowering was somewhat better? 2016: more Mild but sudden severe freezes in Feb & Apr did major damage 2017: very Mild through Feb; H.macs began bud-break way too early, March has been unseasonably Cold Many morning low temps in mid-teens; March consecutively Tip Bud failure of 80% or more fortunately, many H.mac Cultivars have bloomed well off the Stem Buds of the Lateral Nodes 5. 1

2 Hydrangea Species Review it s not enough to just know blue Arborescens Paniculata Quercifolia Anomala Serrata Macrophylla 6. Definitions Deciduous All the Common Hydrangea Species are deciduous - losing their leaves in the fall with decreasing photo period and frost and remaining dormant through winter. Old Wood Macrophylla & Serrata flower buds form during late summer - early fall but typically don t become flowers until the following summer. New Wood Arborescens & Paniculata flowers form and bloom in a single growing season. Some Macrophylla cultivars also develop blooms on new wood. MH = Mophead Bloom, LC = Lace Cap Bloom 7. Arborescens - Old Time Favorites A hardy native American hydrangea species - hardiness zones 4 to 8 Mid to large bush of generally rounded habit - 3 to 6 ft. height & width Plant can be floppy in form due to heavy blooms on slender stems A better species in the ground than in a container can take 2 to 3 years to look good after planting, likes sun but grows well in some shade ANNABELLE is most popular cultivar with large white mopheads appearing in early summer on new wood = 100% blooming guaranteed Blooms mature to palest lime green and/or pink depending on variety and exposure, color unaffected by soil ph. Newer cultivars have better plant form with more upright habit. Incrediball Invincibelle Spirit Annabelle Moultiers, France 8. Pruning Best Practices H.arborescens Early Spring is the most common pruning time, but Fall pruning spreads out the gardener s work-load. H.arborescens flowers on new wood; buds develop in early spring with blossoms following about the same time as H.macrophylla. Prune primarily to achieve and maintain good plant form. Major stem cut-back produces fewer but larger blooms; keeping a basic stem framework leads to better overall bloom vs. plant form development. H.arborescens planted in groups tend to colonize with new growth developing between main plants. This is good as it creates improved stem support & appearance

3 Paniculatas - More Deserving Asian mountain origin from higher elevations, very hardy - zones 3 to 8. Typically strong growers - 5 to 10 ft.plus height & width in bush form, great specimen plants as standards (tree form). Best full sun hydrangea species plus best drought tolerance. Very long-lived; have seen still vital 100 year old plants. Flowers on new wood = 100% blooming guaranteed. Panicle shaped blooms typically open white with maturing shades of lime green to pink to mauve, flowering from mid summer to mid fall. Bloom color unaffected by soil ph. Pruning Best Practices H.paniculata Early Spring is the most common Pruning Time but doing so in the Fall spreads out the total pruning work-load. Also minimizes winter storm effects, deadheading the large blooms prevents snow and ice stem damage. Panics flower on new wood; flower buds form in early spring with blossoms following in July and August. Prune primarily to achieve and maintain good plant form. Be brave! Many Panics are strong growers and substantial stem material must be removed to control plant size. Grandiflora Limelight Quercifolias - The Oak Leaves The other American native; from the mountains of Alabama, Georgia, and Tennessee, growing in the shady understory of tall southern pines. Large, cold hardy (zone 5) bush form plant of moderate habit, 5 to 10 ft. height & width. Newer dwarf cultivars have more bush-like form, 4 ft. height & width. Elongated cream colored flowers appear early summer on second year wood (like macrophyllas), blooms mature to shades of lime and pink to mauve. Bloom color unaffected by soil ph. Leaves are large and oakleaf-like turning shades of rust to burgundy in fall. Prefers some shade - a sheltered site; does not like wind, but needs warmth to flower well. Pruning Best Practices H.quercifolia H.quercifolia flower on old wood, generally only moderate pruning is required. Best to let plant develop naturally as in native woodland setting. Newer hybrids exhibit a more contained bush form. Pruning best done in the spring (late winter). Deadheading old blooms in late fall can reduce snow and ice damage. Snow Queen Snowflake

4 Anomalas - The Climbers Very hardy and long-lived - zones 5 to 9 Plant growth and flowering density can be slow for first 3 to 4 years Good climbers on stone walls, trees, and trellises - can reach heights of 35+ ft. Earliest hydrangea species to bloom; large, open white lace cap flowers in early summer on upper branches, short but stunning blooming period Glossy green leaves in summer; after leaf-drop in fall, tortuous multicolored bark makes an attractive presence in winter Pruning Best Practices H.anomola (The Climbers) Climbers are strong growers chosen mainly for their plant form and texture; flowering is secondary. Typically pruned to contain and direct growth. Spring after flowering - is the Preferable Pruning Time! Prune anytime to contain growth. subspecies PETIOLARIS Serratas - Delicate But Hardy Hardy species of Asian mountain origin growing in the forest understory. More cold-hardy than H.macrophylla - zones 6 (maybe 5?) to 8. Hybridizes well with H.macrophylla; often utilized in newer rebloomers Prefers shadier locations at least a half day of shade; prone to leaf spotting in high sun locations. Upright bush of rounded habit, 2 to 5 ft. height & width. Mostly delicate lace cap flowers with only a few mophead choices. Blooms early summer almost totally on old wood. Slightly subdued bloom color range - whites, pale greens, pinks, blues and some reds depending on soil ph and cultivar. Bluebird Blue Billow Preziosa Blue Deckle 21. Pruning Best Practices H.serrata (The Mountain Hydrangea) Pruning Best Practices H.serrata H.serrata is a close cousin of H.macrophylla, making for many similarities in pruning Late Winter, early Spring is the Best Time to Prune Many cultivars are densely wooded with stems virtually stacked together Attempt must be made to thin out the dead wood and to open the plant s basal crown to encourage new growth Species blooms almost exclusively on old wood, but buds show good cold hardiness with strong survival rate 22. 4

5 Pruning Best Practices H.macrophylla (The Charmers) The H.macs are Soooo Easy to LOVE! H.Macrophyllas The Charmers Maritime Japan origin in temperate climate, plant hardiness zones 5 to 9. Preforms well in sunny locations along NE Coast - at least half a day - with some cultivars flowering well in full sun. Upright bush of generally rounded habit, 3 to 6 ft. height & width. Superb mophead flowers with great color range - whites, pinks, blues, purples, and reds; lace cap flowers also appealing in texture and color Macs flower early summer on mainly old wood with selected reblooming cultivars producing well into fall. Soil ph can effect bloom color and intensity. H.macrophylla Mathilda Gutges 25. Nikko Blue Mathilda Gutges Kasteln & Sketch Brestenberg 28. H.Macrophyllas The Charmers BUT, Macs are the least cold hardy of major hydrangea species!! Flower buds generally develop in Fall MUST survive Winter to Flower the following Summer H.macs don t like it excessively Cold or Hot or Sudden Temp Changes Winter Winds are Equal Enemy of Cold Temps; Cold Dry Air Kills Buds Bud-Break occurs very easily, often too early; First Species to do so in Late Winter, easily vulnerable to spring frosts Bud Hardiness is NOT the same as Plant Hardiness; plants may survive in zone 5 but exposed buds survive only to minimum of zone 6 Pre-Pruning Clean-up; Shop Vacuum Unit equipped with crevice tool Before After Magical Opal LD BigEasy Enchantress CL Venice 29. STEP 1: Late Winter, Early Spring Pruning 31. 5

6 This new basal growth is clear evidence of the essential regeneration process STEP 2: Detail Pruning Removing Winterkill & Deadwood This After view is a much different plant retaining only vital stem material STEP 1: Late Winter, Early Spring Pruning STEP 3: Summer Pinch Pruning STEP 3: Summer Pinch Pruning Pinch Prune at these Locations 37. New stem growth developed from summer pinch pruning Pruning non-flowering stems (and sun-burned blooms) develops more stems and flower buds for next year s blooming. This pruning should be done selectively; typically in July on the Cape and SE Mass

7 STEP 3: Summer Pinch Pruning Pinching is the removal of extra or errant growth on selected non-flowering stems - often to re-expose the existing blooms, and to create a more balanced plant form. On mature plants, strong stems growing above the blooming stems, can be checked to improve plant form and promote additional branching and bud development. Best done in July in our region to insure adequate development of new wood during the balance of the growing season. Works Especially Well on the Reblooming Varieties! H.mac. BloomStruck Bailey Nurseries 39. Pruning Best Practices H.macrophylla Take the Seasonal STEP Approach Pruning is Part Science and Part Aesthetics. STEP 1: Late Winter, Early Spring before Bud-Break - is the time to perform old wood removal surgery on the H.macrophylla species. STEP 2: Mid-Spring after tip and stem buds have leafed-out - remove winterkilled buds and stems, cutting-back preferably to First Pair of Live Buds. STEP 3: Pinch Pruning in July can increase bud development for next season s growth and bloom potential. Better Pruning Yields Better Blooming! 43. Other Possibilities Better Solutions for Poor H.macrophylla Blooming Select the repeat blooming (remontant) cultivars like the Endless Summer Series The Original, Twist-N- Shout, BloomStruck Other varieties to consider Penny Mac, Lady-n-Red, Decatur Blue, David Ramsey Plant more H.paniculatas! - and arborescens, quercifolias, and serratas too. Grow in Containers! Easy to Protect from Winter, Enjoy Reliable Blooming EVERY Summer. 44. Hydrangea Macrophylla Overcoming Winter Damage Reliable Blooming via Container Growing The Pot-in-Pot System 46. 7

8 Container Planting Makes Total Sense H.Macrophyllas do very well in pots. Easy to hand water, fertilize, and prune. Plants can prosper in same pot for 4 to 6 years if well cared for. Can be root pruned and potted up - larger pot size - as plant & root ball expand. Readily moveable to adjust for sun / shade changes, wind direction, etc. Select pot material & color to provide thermal insulation & solar reflectance. Can be a PnP arrangement. Constraining the plant s root mass has promoted increased bloom density with some cultivars. Potted Plant in Australia Touring Garden Heinrich Siedel in Wine Barrel Cloud Hill Garden, Dandenong Ranges near Melbourne, VIC, AUS Big, strong plant grown in same pot for at least 10 years. Growing at 1500 foot elevation under light shade. Good bloom count showing excellent antique color. Note exposed root condition and large volunteer section to left In-Ground Pot in Pot Container Systems 2 to 3.5 Height Diff. Promotes Air Pruning of Root System In-Ground Pot in Pot Container Systems In-Ground Socket Pot Drop-In Plant Pot Plant Roots Stay in the Plant Pot Pot in Pot in BIG Pot Many Benefits! Easy to Create Custom Soil Mixture Easier & More Effective Watering and Fertilizing Insulates Root System - A Big Plus Easy to Replace Tired Plants with New Bloomers Easy to Remove for Winter-Over 3 to 5 gal Plant To be Re-potted Into larger Drop-In Plant Pot Drop-In Plant Pot In-Ground Socket Pot

9 Prepping a Deco Pot for a PnP System Fill bottom of Deco Pot so Rim of Plant Pot is Level with Deco Pot Finished Planting! Coarse Pine Bark Fill Rim Gap to center Plant Pot; leave 4 depth space for Finished Potting Mix Overcoming H. Macrophylla Winter Damage Reliable Blooming via the PnP System PnP Systems can be In-Ground or in a Deco Container. In-Ground option utilizes the drop-in plant pot inside the inground socket pot. Deco Pot option can be a single plant pot inside the Deco pot or a drop-in plus socket (2 pot arrangement) to enable easy plant exchanges. The depth difference between the drop-in and socket pots creates the critical void space for the plant roots to airprune and remain within the plant pot. This air-pruning facilitates removal of the plant pot for winter storage and for replacement of tired plants with fresh bloomers. Overcoming H. Macrophylla Winter Damage Reliable Blooming via the PnP System Plants may be moved under cover only after they have totally defoliated typically after Thanksgiving on the Cape & SE Mass. Only the plant pot is moved for winter storage. Winter storage can be in any unheated area garage, cellar, shed - that moderates temperature extremes and eliminates wind effect. Temp is critical: Ideally 35 to 40 degrees. 45 should be considered a maximum. Lower temps mid 20 s - okay too but must be constant

10 Overcoming H. Macrophylla Winter Damage Reliable Blooming via the PnP System Storage area may be dark; the plants are dormant and do not need light. Water only very minimally, max. once a month. Plants will awaken in February as daylength increases and may be moved to a sunlit area with temps gradually rising into the 50 s and then 60 s. Watering frequency increases as plants begin to grow April 15 is likely the local date to move plants outside, but this is not absolute. Delay if weather is cold and/or windy. Many Thanks!! 58. Mal Condon The Hydrangea Guy malcondon@comcast.net (508) (m) 10