Advice
Frequently
asked Questions (FAQ):
1.
Why does my
hydrangea not bloom?
The old fashion French Hydrangeas which can
either be blue or pink, form flower buds on previous
year’s growth.
Therefore, doing any severe trimming in
winter or spring and removing this wood also removes
flower buds.
Hydrangeas also have a tendency to start
leafing out early when we have some warm days and
are subject to dieback during late freezes which can
also kill the wood where the flower buds will be
formed.
In our area, the best French Hydrangea type is the
new Endless Summer Hydrangea which will bloom on old
and new growth.
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2.
Why do all the
dogwoods I plant die?
Our native white
dogwood is found naturally underneath taller shade
trees and performs best when it has light shade from
the hot afternoon sun.
Dogwood borers are much more prone to attack
trees planted in the sun because the trees are
usually stressed and these insects prefer to lay
their eggs in warm and sunny spots.
Soil conditions also affect dogwoods, as they
prefer a richer, well drained soil rather than the
compacted clay most of us have in our yards.
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3.
What is causing
the leaves to drop off of my roses?
Roses typically
are subject to all kinds of disease and insect
problems.
The most common fungus disease is black spot
which causes dark round lesions of the leaves and
when left untreated eventually will cause the leaves
to drop.
To prevent this condition, the plant should be
sprayed with a mixture of a fungicide and
insecticide every other week through the growing
season and it is best to alternate the types of
chemicals being used.
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4.
Why
are my azaleas wilted even when I water
everyday?
Rhododendrons
and Azaleas are native to mountainous regions where
the ground stays moist but drains very quickly.
Therefore, many times when we plant them in
our home landscapes and do not provide a good soil
amendment, they become water logged at times and
develop a root rot disease which slowly or
immediately kills the plant.
Before planting, make sure the bed area is
raised and has been modified to allow for proper
drainage but also be sure to water once a week
during hot dry summers because these plants are very
shallow rooted.
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5.
What is
wrong with my evergreens that are turning brown?
Spruces,
Junipers and Arborvitaes are beautiful landscape
specimens because they hold their foliage year
round.
However, most of these species prefer a cooler
climate and sometimes struggle in the hot and dry
summers we have.
Unfortunately, this stress makes the plants
even more susceptible to pests like bagworms, spider
mites, scale and even disease.
A spray regime of Triple Action which has an
insecticide, miticide, and fungicide all in one will
help prevent these problems if done on a monthly
basis during the growing season.
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6.
I have a hedge of
yews and two in the middle are dying, why?
Yews like the
azaleas prefer a very well drained soil and
amendment should be added to our clay soils before
planting.
More times than not in the spring we get lots
of rain and our soils become water logged making the
conditions right for development of root rot
disease.
Usually this disease becomes visible in plants in
the summer when they are under heat stress and the
pathogens have already damaged the roots and the
plants start to die.
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7.
When is the best
time to trim my shrubs?
For evergreen shrubs like holly and boxwood,
trimming can be done almost any time, but keep in
mind that pruning in extreme hot weather will likely
result in some foliage burn and pruning after
September could cause an explosion of new growth
that could be damaged by a freeze.
For flowering shrubs like crapemyrtle,
forsythia and azaleas, follow this simple rule- any
spring flowering shrub should be pruned in early
summer and most summer flowering plants should be
cut back in late winter or early spring.
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8.
When and how often
do I spray for Japanese Beetles?
Japanese Beetles
are troublesome pests which love to eat roses,
crapemyrtle, cherry and plums in particular.
Start spraying with Sevin around the end of
May or when you first notice holes in the leaves of
the plants.
Spraying may have to be done on a weekly or
biweekly basis depending on the rainfall for about
6-8 weeks.
Do not use traps for these insects as the
pheromones used in the traps will draw more of the
beetles to your garden.
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9.
When should I
fertilize?
All trees and
shrubs should be fertilized with a slow release
fertilizer in late February or early March, and
again around the first of June if the weather is not
too hot and dry.
Annual and Perennial flowers are heavy
feeders and should be fed with a water soluble
fertilizer every other week during their growing
season.
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10.
Why are the leaves
on my azaleas turning white?
Azaleas
are prone to numerous insect pests but one of the
most common is Lace bugs.
The insects suck out the chlorophyll from the
leaves on the underneath and the leaves take on a
grayish appearance.
Insecticides can be used to treat the pests
with a thorough spray application to the bottom of
the leaves.
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11.
What
can I do for yellowing leaves on my hollies and
azaleas?
These broadleaf
evergreens prefer an acid soil and occasionally need
some amendments to assure the right pH is present.
Apply aluminum sulphate around the plants in
the spring and summer to insure the soil is acidic,
and apply liquid iron as a spray on the leaves to
compensate for any iron deficiencies.
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12.
How often should
I water my trees and shrubs?
Newly planted
trees and shrubs should be watered once or twice per
week during the hot and dry spells of the summer.
These plants generally need about an inch of
water per week so any time we go a week or two
without rain, watering is recommended.
Established trees and shrubs that have been
planted for 2 or3 years need only be watered during
drought conditions.
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13.
Why are my annuals
turning yellow and dying?
Newly transplanted annuals are susceptible to
over watering.
These plants
have not had a chance to get roots established and
creating conditions that are wet can lead to root
disease.
Also sometimes we have weather conditions in early
May that are very cool and wet which lead to disease
development and the detriment of the plants.
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14.
How can I get
rid of Bermuda grass in my flower bed?
Bermuda grass is
an excellent turf for lawns, but can be an invasive
weed in flower beds and landscaping.
We have an herbicide called Grass Killer
which can be sprayed over flowers and shrubs and not
hurt those plants while killing the weedy grass.
Be advised that more than one application
might be necessary.
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Other important things to remember:
All new plantings should be
water thoroughly 1 or 2 times a week during the hot,
dry summer months if we do not get at least an inch
of rain.
Fertilizing of all plants is
best done in early March with a slow release 12-6-6
fertilizer.
This will last about 3
months, so be ready to fertilize again in June and
August.
Minor trimming to remove
broken or fast growing branches can be done at
anytime on all plants.
The best time to prune all
flowering shrubs is right after they finish
blooming.
Evergreens can be pruned at
almost anytime, but be aware that pruning in spring
will encourage fast growth and pruning in the summer
may result in some sunburn of foliage.
Tree pruning is best done when
there are no leaves present on the tree, but be
aware that spring blooming trees have already set
buds and you will be cutting off flowers.
Three major things can cause
yellowing of plants: insects, poor fertilization, or
poor drainage.
Check the upper and lower surface of the
leaves for the presence of insects.
Keep a note or record of when and what kind
of fertilizer was last applied.
To determine if there is poor drainage, was
there standing water or excessive moisture present
during the winter months.
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