hydrangea question
Heidi
My husband and I moved to a home in RI last fall. We have 4 or 5 blue
hydrangea bushes in our yard. One of them is loaded with flowers, a few of
them have a small number of flowers and one of them has no flowers at all.
I'm wondering what I should be doing to take care of our hydrangea bushes.
I've looked at several websites but I'm not finding much about care of
hydrangeas. Should I have pruned them?
I'd appreciate any advice...
Thanks,
Heidi
Vox Humana
"Heidi" <ride...@ride.ri.net> wrote in message
news:9hnm9p$rdb$1...@saturn.services.brown.edu...
> Hi,
> I'm wondering what I should be doing to take care of our hydrangea bushes.
Here is some good general advice:
--------------
http://www.uri.edu/ce/factsheets/sheets/hydrangea.html
General Care:
Hydrangeas are workhorses in the garden. They produce sumptuous petals of
color to add beauty to your garden. But they need not be forgotten once
their flowers have died. Hydrangeas can be captured easily in dried flower
arrangements, providing the last gasp of the summer garden. Pick the blooms
on a clear dry day in late summer and hang to dry. H. macrophylla and H.
paniculata 'Grandiflora' are especially good for drying.
Most species of hydrangeas can be grown in either full sun or partial shade.
They are resistant to most insects and diseases. They can be grown in a wide
range of soil but prefer a rich, moist soil and should be planted where
watering will not be a problem. Avoid dry windy sites, as their large, soft
leaves lose water quickly, especially on hot, windy days, causing the
foliage to wilt.
Flowers are produced on the new growth; therefore, it is important that
hydrangeas be given some care each season to ensure that vigorous new growth
occurs. Irrigate plants weekly to replace moisture loss. Prune flower stems
after they have bloomed.
Fertilize hydrangeas in early spring with a complete granular fertilizer at
the rate of 2 pounds per one hundred square feet. Apply fertilizer as
broadcast top dressing. During long periods of drought, water thoroughly
each week.
Pruning:
There are many different types of hydrangeas; many require different methods
of pruning. First, one must know the identity of the hydrangea in the
landscape, so the proper pruning procedure can be implemented.
Hydrangea arborescens 'Grandiflora' -- Hills-of-Snow Hydrangea
Prune hills-of-snow hydrangea to the ground line each winter or early spring
because it flowers abundantly on new growth, and is frequently killed back
during winter. If a larger shrub is desired (3+ feet) and/or it is not
killed back over the winter, prune less severely. Remove certain branches to
the ground; cut others back at varying heights from 1 to 3 feet.
Hydrangea paniculata 'Grandiflora' -- Pee Gee Hydrangea
This is the most commonly planted hydrangea because of its massive displays
of large white flowers in mid-to-late summer. They gradually turn to pink
and remain on the plant in a semi-dried condition long after the leaves have
fallen. Pruning involves the removal of dead flowers, if unattractive, and
an annual corrective pruning of vigorous shoots. Thin and/or cut back the
previous season's growth in late winter or early spring, since flower
clusters occur on newly developing branches. Without regular pruning, this
hydrangea can rapidly become quite overgrown and out of scale in the
landscape. It can, however, be developed into a single or multi-stemmed tree
form.
Hydrangea macrophylla -- Hortensia or Florist Hydrangea
This is a commonly grown hydrangea with large globe-shaped flowers. It is
frequently forced by florists and sold as an indoor pot plant during the
spring season. Once moved outdoors, however, color is dependent upon the pH
of the soil in which it is grown: blue if acid; pink if alkaline. There are
also several white-flowered cultivars. Pruning can be accomplished at two
different times. Late summer is more desirable, since most hortensia types
flower only from the end buds of upright or lateral shoots produced during
late summer and fall of the previous season. Prune as soon as the flowers
have faded and strong shoots are developing from the lower parts of the
stems and crown. Remove at the base some of the weaker shoots that are both
old and new. Always try to keep several stems of old productive wood, with a
sufficient number of stout new stems that will flower the following season.
Early spring pruning (March), although acceptable, will result in the
sacrificing of bloom for that growing season.
Pruning this species too late in the fall (after September) is harmful. New
growth, both vegetative and reproductive, will not develop proper maturity.
Hortensia is a good seashore shrub; flowering is more profuse in an open,
sunny location. This, however, increases its vulnerability to bud killing.
Winter protection of the plant should be initiated in December to preserve
buds for next year's flowering. Tie the shoots together and wrap with
burlap. If left unprotected, delay any spring pruning until the buds swell
in order to determine which wood needs to be removed, and then cut back to
below the point of injury.
Hydrangea quercifolia --Oakleaf Hydrangea This plant is grown primarily for
its handsome oak leaf-shaped foliage, excellent fall color, attractive
flowers and interesting winter bark. It is ideally suited to a lightly
shaded or protected location, and if grown in an exposed site, it is subject
to some winter dieback. Prune back in early spring to remove dead wood. Cut
back to below the point of injury and remove old wood to the base.
Hydrangea anomala petiolaris -- Climbing Hydrangea Climbing hydrangea is a
desirable mid-summer flowering woody vine that attaches itself by aerial
roots to brick, masonry or wood. It requires little or no pruning. If
certain shoots have grown out of bounds, reduce their length in summer.
Frequently, concern is expressed about climbing vines that may be inundating
a tree and causing irreparable damage. There has never been a proven case of
damage occurring from climbing hydrangea, however.
Color Confusions:
The color of the pink and blue varieties is determined by the degree of soil
acidity. Pink varieties develop color best in the greenhouse at a soil pH of
6.5 to 7.0., while the best blue color occurs at pH 5.0 to 5.5.
The hydrangea flower is small and insignificant but is surrounded by showy
bracts. The anthocyanin pigment will be pink or blue, depending upon the
incorporation of either iron or aluminum in its molecules. Insufficient
aluminum is absorbed by the plant at a pH of 6.5 to 7.0 so iron is used.
As the pH drops to 5.0 to 5.5, aluminum becomes more soluble, is absorbed by
the plant and becomes part of the anthocyanin molecule resulting in blue
coloration.
White hydrangeas contain no pigment in their sepals (although some may
develop as the blossom ages). They may be grown as either pink or blue, the
only indication being given by the small petals. Common white varieties are
Sister Therese and Regula. Rose Supreme, Merritt's Supreme and Merveille are
examples of varieties which can be blue or pink depending on soil
conditions.
To maintain pink coloration, enough limestone should be incorporated in the
soil at the time of planting to keep the pH at the above levels.
The aluminum necessary for blue color will become soluble in nearly any soil
at a pH of 5.0 to 5.5. Depressing the pH with aluminum sulfate will also
supply soluble aluminum. Since soluble phosphates precipitate aluminum, a
fertilizer containing low phosphorous or none at all should be used (13-0-20
and 15-0-15 are examples).
While these methods of changing the flower color can be used, it's not a
wise idea to do it indefinately. You risk severely altering the soil pH
thereby making it difficult for the plant to utilize nutrients. Always get
the soil tested before altering it. Refer to GreenShare Factsheet on soil
testing for more information. If you really like different colors in your
hydrangeas then get many different cultivars!
Holiday Plants:
If you obtain a potted hydrangea for Easter or Mother's Day in full bloom,
keep the soil moist at all times as this plant has a high water requirement
and tends to dry rapidly in the home. It should also receive direct light.
After the flowers fade, they may be removed and the plant treated as a house
plant. When danger of frost is past, it can be planted in a sheltered
location in the garden. Shelter is necessary because the hardiness of this
plant is questionable in our northern gardens. This plant forms flower buds
in the fall like forsythia and dogwood. It is these buds which freeze out or
are destroyed in colder climates. Many times the plant will survive and
produce green leaves, but no flowers. Planting in a sheltered location plus
covering the plant with burlap will offer some protection. If you wish to
improve the probability of flower bud survival, you may wish to try this.
When danger of frost is past, plant in a sheltered place in the garden. On
the 4th of July, prune to 3 to 5 inches from the ground. The plant will
produce short branches terminating in a dormant flower bud. Before the
temperature falls to 25 degrees F, place a screen around the plant. Fill
this with an insulating material such as coarse peat moss, vermiculite or
bark. More material may be added if it settles during the winter. Remove
this protection when the crocuses flower but protect on cold nights. If you
are lucky, the flower buds will survive. In any event, you should have a
pretty foliage plant.
If you are successful in over-wintering these varieties, fertilize with your
usual garden fertilizer (such as 5-10-10). If you desire blue flowers, have
your soil tested as a low pH is needed. 'Nikko Blue' is a common true blue
variety. To lower the pH, apply aluminum sulfate or sulfur. Avoid over
acidification and "playing" with the soil chemistry and plants. For pink
flowers, limestone may be necessary to raise the pH since soils are
naturally acidic in Southern New England. Always choose varieties for the
colors you like.
If you are not successful in over wintering greenhouse varieties, hardy
hydrangeas are available. Some are: Hills of Snow Hydrangea (H. arborescens
Grandiflora, similar to the greenhouse varieties), Pee Gee Hydrangea (H.
paniculata Grandiflora) or Climbing Hydrangea (H. anomala petiolaris).
Adapted by Rosanne Sherry, URI Master Gardener Coordinator, 7-98
Based on fact sheets from Cornell-Suffolk Co. Long Island New York
Cooperative Extension, Connecticut Cooperative Extension and Virginia
Cooperative Extension.
Iris Cohen
with flowers, a few of them have a small number of flowers and one of them has
no flowers at all. >>
Hydrangeas are funny. Do some detective work & see if there are any differences
in the locations of the bushes, amount of light, soil type, etc. Don't prune
them except in the spring to remove completely dead stems. They bloom from old
wood. Give them plenty of water and acid fertilizer, mulch them, and if you are
in a cold area, put rose cones over them in the winter (you will have to prune
them just enough to fit the rose cones, but that won't matter).
Iris,
Central NY, Zone 5a, Sunset Zone 40
"It is forbidden to live in a town which has no greenery." Jerusalem Talmud,
Kiddushin 4:12.
Steve @ Erin
iris...@aol.com wrote on 7/2/01 8:29 AM:
My Hyndrangea is finally budding, but has small brown spots on the leaves.
Any idea what this is?
Erin, z.6
Jim Voege
"Iris Cohen" <iris...@aol.com> wrote in message
news:20010702082944...@ng-ma1.aol.com...
> << We have 4 or 5 blue hydrangea bushes in our yard. One of them is
loaded
> with flowers, a few of them have a small number of flowers and one of them
has
> no flowers at all. >>
>
> Hydrangeas are funny. Do some detective work & see if there are any
differences
> in the locations of the bushes, amount of light, soil type, etc. Don't
prune
> them except in the spring to remove completely dead stems. They bloom from
old
> wood. Give them plenty of water and acid fertilizer, mulch them, and if
you are
> in a cold area, put rose cones over them in the winter (you will have to
prune
> them just enough to fit the rose cones, but that won't matter).
>
*Some* Hydrangeas bloom on old wood. This is certainly true of H.
Macrophylla. However, the species of other popular varieties such as H.
arborescens 'Annabelle' and H. paniculata 'Pee Gee' (Grandiflora) both
flower on new wood and can be pruned quite severely in the Spring, depending
on whether you want lots of flowers or larger flowers.
--
Jim Voege
Remove nospam for reply
Lenora C
I moved to this house in March and there were a lot of existing plants I
did not know where. Well while pruning back my lilac bush earlier in
the spring I found this small (about 4 inch) type bush. It had small
bits of old wood but nothing growing on the old just then new shoots. I
dug around the base a little and there was a nursery tag stating only
Hydrangea. So I transplanted it to the West side of my house and it is
now about 8 inches tall. I have no idea what type of hydrangea it is and
I know I will probably not get much from it this year but am anxious to
see what next year brings.
Lenora
in zone 5