This is really a pretty basic question. But my wife and I are a
little new at this, having bought our first house a year ago. We're
doing our best to renovate our yard, which was pretty neglected by the
previous owners.

In our front yard, we have an ancient-looking but previously vigorous
rhododendron, and nearby (about 6-8 feet away) I planted a fairly
young (~5 feet tall) emerald green arborvitae last October. Both
looked nice and green last year.

This spring, we've planted various other small flowers and grasses in
the same area, following the instructions provided for spacing and
watering. I've also given these flowers some all-purpose Miracle-Gro
(again, diluted according to the instructions and given no more than
once every two weeks) and I've thrown some "Holly Care" fertilizer
around the tree and rhododendron, which are supposed to like that
particular fertilizer (it's for acid-loving evergreens.) As the
temperature has warmed up, though, both the tree and the rhododendron
have started turning brown and losing some leaves. The rhododendron
actually started growing a new layer of leaves on top, but all of
these have now turned brown from the outer edge, with the rest of the
leaf being a pale green. The older leaves seem to be ok so far, it's
the new leaves that are looking pretty sad. The arborvitae is
browning from the bottom, but I swear the rest of it also looks a
little thin compared to when I got it.

The other plants in that area are too new for me to really judge how
well they're doing; some do seem to be doing better than others,
though.

We've had some weird weather in the past month or two here in the
Northeast; it was bitterly cold for a while, then we had some
torrential rains (like 4 inches in one day, for two days). Because it
rained so hard for a while, I didn't water at all for about 10 days.
That's when I started noticing the browning, and the soil was cracking
from being so dry on top. I then watered well two days in a row last
weekend, but I don't know if that was right or wrong. The soil itself
is bone dry on top and never seems to stay wet, but underneath it
feels moist (not wet). Keep in mind the rhododendron has been in that
spot for years, and done well, so I don't think the soil itself is the
problem.

My problem is I don't really know how much is a "normal" amount of
water. My wife and I have actually been having some mini-arguments
about it; she thinks that unless there's a drought, you don't really
water at all because all of these things grew in the wild at some
point. I think she's wrong, and in fact all the plants she tries to
grow herself end up dead. (I of course point this out every time we
talk about this.) I usually water trees once a week, and other plants
a couple times a week.

So does it sound like we're overdoing it or underdoing it? How often
should we be watering? (And maybe more important - who is right, me
or my wife?)

Thanks...

Jeff

To water, just water enough to moisten the non-woody absorbing roots. The
non-woody absorbing roots absorb water with elements dissolved in it. They
are mostly in the upper four inches of the soil. During drought the biggest
problem is over watering.
A very good question. I would be careful about using alot of nitrogen
fertilizer about your trees. Large amounts of the element nitrogen can
predispose your tree to sucking insects. The Christmas tree industry
suffers from that predisposition often because the use large amounts of the
element nitrogen to make the trees grow bigger and faster. That places the
trees in a predisposition for sucking insects. Then they spray for sucking
insect. Over fertilizing with the element nitrogen is very common. For
more on predisposition see here.
http://www.treedictionary.com/DICT2003/shigo/ARM.html

Sincerely,
John A. Keslick, Jr.
Arborist
http://home.ccil.org/~treeman
and www.treedictionary.com
Beware of so-called tree experts who do not understand tree biology.
Storms, fires, floods, earthquakes, and volcanic eruptions keep reminding us
that we are not the boss.


wrote in message
oups.com...
This is really a pretty basic question. But my wife and I are a
little new at this, having bought our first house a year ago. We're
doing our best to renovate our yard, which was pretty neglected by the
previous owners.

In our front yard, we have an ancient-looking but previously vigorous
rhododendron, and nearby (about 6-8 feet away) I planted a fairly
young (~5 feet tall) emerald green arborvitae last October. Both
looked nice and green last year.

This spring, we've planted various other small flowers and grasses in
the same area, following the instructions provided for spacing and
watering. I've also given these flowers some all-purpose Miracle-Gro
(again, diluted according to the instructions and given no more than
once every two weeks) and I've thrown some "Holly Care" fertilizer
around the tree and rhododendron, which are supposed to like that
particular fertilizer (it's for acid-loving evergreens.) As the
temperature has warmed up, though, both the tree and the rhododendron
have started turning brown and losing some leaves. The rhododendron
actually started growing a new layer of leaves on top, but all of
these have now turned brown from the outer edge, with the rest of the
leaf being a pale green. The older leaves seem to be ok so far, it's
the new leaves that are looking pretty sad. The arborvitae is
browning from the bottom, but I swear the rest of it also looks a
little thin compared to when I got it.

The other plants in that area are too new for me to really judge how
well they're doing; some do seem to be doing better than others,
though.

We've had some weird weather in the past month or two here in the
Northeast; it was bitterly cold for a while, then we had some
torrential rains (like 4 inches in one day, for two days). Because it
rained so hard for a while, I didn't water at all for about 10 days.
That's when I started noticing the browning, and the soil was cracking
from being so dry on top. I then watered well two days in a row last
weekend, but I don't know if that was right or wrong. The soil itself
is bone dry on top and never seems to stay wet, but underneath it
feels moist (not wet). Keep in mind the rhododendron has been in that
spot for years, and done well, so I don't think the soil itself is the
problem.

My problem is I don't really know how much is a "normal" amount of
water. My wife and I have actually been having some mini-arguments
about it; she thinks that unless there's a drought, you don't really
water at all because all of these things grew in the wild at some
point. I think she's wrong, and in fact all the plants she tries to
grow herself end up dead. (I of course point this out every time we
talk about this.) I usually water trees once a week, and other plants
a couple times a week.

So does it sound like we're overdoing it or underdoing it? How often
should we be watering? (And maybe more important - who is right, me
or my wife?)

Thanks...

Jeff

[snip]
My wife and I have actually been having some mini-arguments
about it; she thinks that unless there's a drought, you don't really
water at all because all of these things grew in the wild at some
point. I think she's wrong, and in fact all the plants she tries to
grow herself end up dead. (I of course point this out every time we
talk about this.)

How often should we be watering? (And maybe more important - who is right,
me
or my wife?)

Thanks...

Jeff

1. There are a lot of variables that you haven't addressed, such as the
type of soil you have, how long you're watering (ie, how much water are you
putting out at one time), etc.

From the tone of your post I infer that you don't have mulch around the
rhododendron. This plant should be well mulched -- 3-4 inches or more --
just make sure that the mulch is doesn't actually touch the trunk of the
plant. That will keep the plant cool and moist without being soggy. It
also sounds like you're using too much fertilizer and possibly too much
water -- either of which can cause the leaf problems you've mentioned.
Suggest one application of a good slow release azalea fertilizer before the
plant goes into bloom and a second application after flowering has
completely finished. That should do it for the year. Miracle-gro every two
weeks is way over-kill, especially for an old established plant.

If the plant is mulched and you have sandy loam, water about twice a week if
there is no rain, for 30-40 minutes with a good garden sprinkler or
installed irrigation system -- not just a hose end into the garden bed.
That should put out about 1/2 - 3/4 " of water, which is enough. You can
measure how much water you're dispensing by putting out a tuna fish tin, cat
food tin, or similar vessel and measuring how much water you collect in half
an hour, then adjust from there. If you have heavy clay soil this schedule
is too much water.

Your plants will probably improve with less attention -- just make sure
they're weeded, mulched, and on a modest irrigation schedule, plus limited
fertilization. Your local extension service probably has information on
fertilizer and water schedules for your plants and your area.

Your wife is on the right track for well established trees and shrubs,
especially if you have native plants. For annuals and newly established
perrenials you will need to make sure they don't dry out -- but too much
water will also rot the roots and kill the plants. Reminding your wife that
everything she plants dies is not a winning tactic and will guarantee that
you always work in the garden alone --

As for your second question, regardless of the facts in the case, you need
to repeat about 10 times a day -- my wife is always right, my wife is always
right, my wife . . .

Regards --

On Apr 25, 10:09 pm, "JimR" wrote:
1. There are a lot of variables that you haven't addressed, such as the
type of soil you have, how long you're watering (ie, how much water are you
putting out at one time), etc.

Type of soil I actually am not sure about, which is why I didn't
mention it, but also why I said the rhododendron has done well in this
location for years. I don't think the ph of the soil is really a
problem, although not knowing what type of soil we have is definitely
one reason I'm confused about watering. It seems like we have several
different kinds of soil in different areas of the house. The soil
where the rhododendron is seems sandy, but I'm hardly an expert.

From the tone of your post I infer that you don't have mulch around the
rhododendron.

No - and I had planned to do this. I don't have much mulch in this
area because it's right up against the house, and everybody advises
against putting mulch next to your house in my area because of the
risk of termites. But I can put a little bit down, I guess, and just
keep the radius fairly small.

But the plant did well without mulch before. It's not like I removed
mulch and now it's dying.

Suggest one application of a good slow release azalea fertilizer before the
plant goes into bloom and a second application after flowering has
completely finished. That should do it for the year. Miracle-gro every two
weeks is way over-kill, especially for an old established plant.

The Miracle Gro is being used on the other plants, which are new and
growing, but I mentioned it because I thought it might be dribbling
over a bit. (The MG package says once every two weeks for most
plants.) I've only actually fertilized the rhododendron with the
Holly Care, and I used less than recommended.

If the plant is mulched and you have sandy loam, water about twice a week if
there is no rain, for 30-40 minutes with a good garden sprinkler or
installed irrigation system

See, from this, it sounds like I'm not watering enough. I water this
plant (and the tree) usually once a week, and less if it rains, and I
don't water them for 30-40 minutes, that's for sure. I water them
until the ground looks like it can't hold any more water, i.e. puddles
start to form and don't immediately disappear. That's usually within
5-10 minutes. Sometimes I just go out there with a gallon can of
water and empty it.

Should the soil be getting completely dry between waterings or should
it be kept moist? And how deep are the roots of a rhododendron?

wrote in message
oups.com.

[snip]


I water this
plant (and the tree) usually once a week, and less if it rains, and I
don't water them for 30-40 minutes, that's for sure. I water them
until the ground looks like it can't hold any more water, i.e. puddles
start to form and don't immediately disappear. That's usually within
5-10 minutes. Sometimes I just go out there with a gallon can of
water and empty it.

Should the soil be getting completely dry between waterings or should
it be kept moist? And how deep are the roots of a rhododendron?


There's too much left out to even suggest a comprehensive answer. The
reference to 30-40 minutes is for a sprinkler that wil add 1/2" - 3/4", but
it sounds like you're using a hose end or jug to deliver a lot of water in a
short time. How much sinks in? How much runs off? (ie, how much is
actually available to the plant?) Is your soil heavy clay that may be
waterlogged, or hardpan that allows all water to run off rather than be
absorbed by the plant? Your rhodo needs both regular, deep watering, plus
good drainage that keeps it from becoming waterlogged.

Here are a couple of references I found --

--Fraser South Rhododendron Society - Rhododendron Basics - What
Rododendrons Require --
http://www.flounder.ca/FraserSouth/b...quirements.asp

(" . . . [It] is important to understand their basic requirements.

First: Rhododendrons must have a constant supply of moisture. You may
occasionally see a rhododendron that will survive without being watered, but
it does so only under protest.

Second: Rhododendrons must never sit in stagnant water. Roots submerged in
poorly oxygenated water will likely die, though a plant may survive through
better drained surface roots. Hot, wet conditions are more dangerous than
cool, wet conditions. That is why a rhododendron will survive in a wet spot
in the Northwest during heavy winter rains but would not survive in a wet
spot in the Southeast's heavy summer rains.

Third: Rhododendrons must be grown in an acid medium (pH 5-6) that is
coarse enough for the roots to have access to needed oxygen.

Understand and provide these three conditions and you will succeed
wherever you live.")

-- Clemson Extension Service:
http://hgic.clemson.edu/factsheets/hgic1073.htm

("Rhododendrons are shallow-rooted plants and require irrigation during
dry periods. This is especially true of those planted in the preceding
spring. Rhododendrons planted in warm weather in sandy soils may require
watering of the root system twice a week during the first year. Newly
planted rhododendrons require regular watering during dry spells for the
first several years.
Pull back a small area of mulch beneath the canopy of the plant and check
the soil moisture level. When the soil feels dry, wet it to a depth of 8 to
12 inches. Use soaker hoses or drip irrigation to slowly water the base of
the plant.

Be mindful that rhododendrons in waterlogged soils will decline and become
susceptible to root rot diseases. It is important to reach a balance between
regular, deep watering and good drainage to promote a healthy plant."

-- Somerset County Chesapeake Watch Planting Requirements and Plans:
http://www.somersetbaywatch.org/PlantingReqs.html

These should help you understand how to treat your rhododendron -- best of
all, consult your extension service Master Gardener program. Regards --