When we plant rhodos and azaleas in our garden, we have to consider how
they grow in their original natural environment. So we have to imitate
their growing conditions as well as we can. Just watering now and then has
no sense. If we have taken the right measures in planting the plants, we
will have to see what happens. In nature the plants and trees provide
themselves with the needed layer of mulch materials, thus keeping the soil
moist and cool. In our garden the conditions as we started are different.
Mulching and watering are coherent things,. Therefore we must take care of
the plants in hot periods and in cold times.
summer watering is an important thing to do. If we mulched well, the soil
will be moist and relatively cool, but after a long period of dry and hot
weather tha plants can give a sign, that they need water. Especcially when
the rhodos have new leaves, they will wilt, showing their need of water.
If this is still the case early in the morning, they need water, that's
clear. As I told before, it is necessary to water not just a bit, but so
long, that the whole rootbal is moist, but not excessively to avoid thet
it is soaked with water. This will cause root rot diseases. In some
regions fall can be very dry and the plants must be watered before winter
to replace water lost from the leaves and be prepared for cold dry winds
periods in winter!
Rhodos and azaleas, planted near some
trees like birches and firs need extra water. they have a shallow root
system and are competitors for water. They need extra care and attention.
This is also true for those plants which are in full sun for the whole day.
You must realize, that it is difficult to water a rootball that is
completely dry - using a dripping system is a good solution. Building a
berm around the plants can prevent the water to soak away. The
message is: do not wait too long to take the right measures for watering
All living creatures, people, animals and plants - need their food,
nutrients. So also rhododendrons and azaleas. But what, and when and how
Especcially in the growing season the plants need to be fertilized. New
plants don't need too much fertilizer the first growing season. And if you
mulch well, the mulch will provide the plants with what they need to a
certain extend. Note, that overfertilizing can burn the roots which can
cause diseases. So, be moderate in fertilizing; as long as the plants grow
and look healthy, they don't need that much. I apply inorganic fertilizer
in a mixed combination of NPK 12-10-18, a general fertilizer. N stands for
nitrogen, P is phosporus and K is kalium, potassium. I will not go into
details, but this combination works well for me. Never fertilize first and
then mulch. Always over the mulch. The root system of rhodos and azaleas
is quite tender and fertilizer directly in contact with the roots is
asking for trouble!
Practice a so called split application - in March one half and later in
June\July the other half. And fertilizing after July stimulater the growth
too much and too long, so the plants will not harden off well enough. So,
not later than July!
There are also special fertilizers for rhodos and azaleas, that's good to
use. They also have magnesium, good for leave colour. You can also use
rotted manure - I use it from chicken, but then in small amounts, because
of the other salts in it. The advantage of organic fertilizer is, that it
contains mostly many trace elements, good for a good growth of the
plants. Understand that it is much better to apply in many times than
everything in one time. Scatter the fertilizer in the droop line of
the plants, not along the stems, where it hardly has sense and could
damage the stem.
Another way of fertilizing is, to use 'Osmocote' or simular trade
marks. This is a fertilizer with a thin layer of resin or so, and it
spends the fertilizer depending on moisture and temperature for 3, 6 or 9
months. It is quite expensive, but works well, especcially when you grow
new plants in a greenhouse!
There is much more to tell about fertilizers, but then you can better read
special literature. Just one last hint about this:"It is better to
use no fertilizer than too much! Definately as long a the plants look
is the best thing for a good growth and fine flowers! For the plants, the
soil, and yourself! Do you like dragging around garden hoses to water the
plants? Do you like to pull weeds? Don't you want to save money on
fertilizers? If so, you are a very special gardener! If you mulch the
right way with the right materials, it has some great advantages:
1. It keeps the soil cool,
especcially in summer;
2. it keeps the soil moist, so you
don't have to water se frequently;
3. It stimulates earthworms and microarganisms to do
their work and decompose the mulch materials;
4. it allows the decomposed material
to give the nutrients out of it;
5. it saves you a lot of work and
time and a painful back;
6. it adds organic matter to the soil
and the roots can grow into it.
can use the following organic mulch materials:
straw - pine bark (nuggets) - pine needles - wheat straw - peanut
hulls - (decomposed) shredded oak leaves - wood chips - sawdust - grass
You can use all these materials, but you have to keep in mind the
particular (dis)advantages of each. If the material is not decomposed,
like wood chips, leaves, grass clippings etc. they rob nitrogen from the
soil to decompose. So, it is better to decompose first. Using just any
leaves means, that they can blow away with the wind and make a mess in
your garden. Shredded materials work better. Another important matter is
how coarse or fine the material is. What we need, is a layer, thick
enough to keep the burnung heat of the sun away and prevent evaporation of
the water. Besides, in the mulching material there must be air enough for
the roots to breath.
So, all these considerations make me prefer shredded Pine and Fir bark
nuggets of different sizes mixed up. Half of the pieces of about 1 to 2
inches, the other half about 3-5 inches. Another benefit is, that it must
not be replenished every year, because the decomposing is quite slow.
Grass clippings can mat and make rain drains away form the shrub If
you want to use grass, weat straw, sawdust etc. you can better
decompose it for a year and then use it. Ask around for local suppliers
what they offer for what prices. You can use expensive materials for the
foreground and and cheaper stuff for the background. But consider, that
cheaper materials have a shorter longevity and must be replenished more
frequently. So, what is really cheaper? And what looks better? I read an
expression of somebody:"Organic matter is the magic elixir". Use
it for your plants and yourself.
Regularely I get questions about pruning rhododendrons and azaleas. They
have grown too high or broad or gardeners want to prevent this. Moreover
they grow more compact when you prune them.
Well, we have to distinguish between pruning to give the plants a better
shape or make them more compacr. Or we want a heavy pruning to resize the
means, that after flowering time, May or June, we cut back the twiggs one
year or even 2 years. Just look at the growth of the last year and cut
back an inch or shorter above last whorl of leaves. Deadheading is also a
form of light pruning as is that you break down the one growth bud when it
is the only bud to expand. It will cause that the other dormant buds at
the end of the stem will expand. All of these methods will not have a
negative affect the flower bud set for next year.
Heavy pruning is a different
story. Sometimes it is better to replace the whole plant, when it has
grown far too big or leggy. You have to consider what happens if you prune
the shrub heavily. Doing this - early spring - in one time will face
big consequences. Normally the shrub has a good cover of branches and
leaves, giving the rootball shelter and shade. Now you are destroying this
balance. After heavy pruning the large rootball has now a small top and
can't spend all the water and nutrients to it. It is not in balance. It is
better to prune in stages, this year the back half and next year the
front back or reverse. Or this year the left half and next year the right
half. And then you can have luck or bad luck. You also have to protect the
surface of the rootball for the heat by mulching heavily. Even then it can
fail. Most of the time the very small dormant buds along the stem will be
stimulated to make new growth, but it can take several years that the
shrub recovers and will flower again. Don't fertilize now or very little!
Sometimes there is no regrowth on the branches but new shoots from the
basis of the roodball.
Deadheading means, that you remove the withered flower clusters with your
thumb pushing on the side of the axis of the flowertruss. The
advantage is, that the plant looks better now and it does not have to
put energy into the developement of seeds. Possibly you get more
flower buds for next year. Deadheading small leaved rhodos and
azaleas is hardly useful and actually not workable. With a large
garden and hundreds of rhododendrons.............
May be a better option for heavy pruning is to transplant a large
rhododendron, but ii is not so easy. Actually it is a waste to mangle a
nice large rhododendron, if you can transplant it. But how? You have to
prepare a new place in the same way as for normal planting a rhodo. Try to
dig out the rootball as large as possible, draw it on a plastic sheet and
pull it to the new place. If this is not possible or too far away, try to
get it on a wheel barrow with the help of some other people and drive it
to the new place. The best time to do so is March\April and October\November
when the plant is dormant. Take extra care for the right soil and mulch
well. Don't fertilize in October\November and wait till next year May\June.
The plant must get used to its new place and make new roots.
mulch!, and water when the plants show lack of water - it is hard to
water a rootball that is completely drought out!
2. water long enough, that the whole rootball is moist, or use a drip
system; don't overwater to avoid diseases.
3. fertilize in March\April and again June\July; not later - the plants
must harden off;
4. don't overfertilize; mulch first, then fertilize, not reverse!
5. as long as the plants grow and flower well, they hardly need fertilizer;
6. mulching is very important - materials: Pine
straw - pine bark (nuggets) - pine needles - wheat straw - peanut
(decomposed) shredded oak leaves - wood chips - sawdust - grass
7. apply it in a layer of 2 to 4 inches, best fine and coarse pieces
8. moderate pruning after flowering, 1 year or 2 years back 1 inch above
the leave whorls
9. heavy pruning in early spring this year 1 half, next year the other
half; mulching needed! Don't fertilize now.
10. transplanting in spring or fall; take the whole rootball if possible;
drag on plastic sheet; mulch!