‘Endless Summer’ hydrangeas provide wave of summer color
Garden writer Ciscoe Morris discusses long-blooming “Endless Summer” hydrangeas and a checkup for dahlia tubers.
Special to The Seattle Times
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In the Garden
Unlike other mophead and lacecap hydrangeas (Hydrangea macrophylla), hydrangeas in the “Endless Summer” collection bloom both on current and older-season wood, resulting in a significantly longer blooming season.
Of the two mophead varieties offered in the collection, “Blushing Bride” produces pure white flowers that blush pink as they mature, while the pom-poms on “Endless Summer” are blue in acid soil and pink in alkaline conditions. The color of the lacecap flower on “Twist and Shout” also varies from blue to pink depending on soil acidity. Hydrangeas in the “Endless Summer” group are fairly trouble-free, but they do have a few requirements to encourage them to put on their best display.
For one thing, in order to bloom well, they need about six hours of direct sunshine, yet require protection from hot afternoon sun. Late spring freezes can damage tender buds and thus delay blossoming. If freezing weather is forecast when buds are swelling, cover the plants with a sheet or row crop cover until milder weather returns.
Flower production is greatly improved by feeding with an organic flower fertilizer in early April. Be careful not to overwater these hydrangeas. The plants in this collection tend to bloom best when they suffer a bit of stress. Water only about once per week, and don’t worry if the leaves wilt a bit in hot weather as they will quickly recover in the evening.
Finally, don’t make the mistake of whacking your “Endless Summer” hydrangea to the ground. When growth begins in spring, symmetrically remove about one-third of the oldest canes by cutting them as close as possible to ground level. Reduce height by cutting the remaining canes back by no more than a third. The extra effort you spend caring for your “Endless Summer Collection” hydrangeas will reward you with a summer long feast of beautiful blooms!
Check on dahlia tubers
This is a good time to check dahlia tubers that you’ve been overwintering in your unheated garage or crawl space. Inspect the tubers for signs of rot or fungus and discard any that feel mushy or look like they’re rotting.
If any of the tubers appear to be shriveling, it means they are drying out. Mist them with a spray bottle and slightly moisten their storage medium; then hope for the best. If they’re still shriveled at planting time, compost them because they aren’t likely to survive.
If you find that the tubers have already sprouted, there are two ways to handle the problem.
One method is to cut the shoots off, leaving a node at the base. New shoots should emerge from the node after planting outdoors, although regrowth and flowering may be delayed two or three weeks. Another way to deal with a sprouting tuber is to pot it. Store the pot in a cool, dark location such as an unheated garage or crawl space.
Hopefully, that will arrest development. If the plant continues to grow, keep it in bright light in your unheated garage, water sparingly and put it outside on nice days. Wait to transplant from the pot into the garden until the dahlia has established a healthy root system, and conditions have warmed up in early May.
Ciscoe Morris: firstname.lastname@example.org “Gardening With Ciscoe” airs at 10 a.m. Saturdays on KING-TV.
About Ciscoe Morris
Ciscoe Morris' column runs Thursdays. His show "Gardening with Ciscoe" airs at 10 a.m. on Saturdays on King 5.