My 24yr old Grapefruit is Sick!!!

I'm looking for some help in saving my 24 year old grapefruit tree. Late last summer it started to decline very slowly, loosing leaves, and branches turning brown. The largest section of the leaf curls up and eventually turns yellow and falls off leaving the part of the leaf closest to the branch in tact for months. New little sprouts turn balck, shrivel up and die. The tree has lost all of it's main foliage now but has one new sucker coming up from the base. There is also some gummosis on parts of the trunk. I've read some other posts in this forum and believe this disease could be very similar to what Sue Darton's Grapefruit had which was posted by her in this very forum on April 14th of 2004. Would love to get in contact with her or "Mr. Shep" - the gentalman on this forum who was advising her what to do.

Please someone help.

Nate

 

Jim (Mr. Shep) monitors this forum, and he should see your post. I would ask how long has the tree been growing in the present medium (potting soil) , without being transplanted into a new medium? What are the ingredients of the tree's potting soil. When was the last time that you flushed out the root zone? Because, your tree is in WI, a state that does not have any of the common citrus diseases, I believe your tree's problem is in the container's root zone. Evidently, you must know a something about growing citrus, as you have been able to keep your tree alive for 24 years. - Millet

 

Also, please tell us where you keep it? IE position/conditions/changes...indoors... outdoors(probably not)

 

The tree has been in the current container (about 20 gal - biggest we could find) with the same soil for about 2 years now. The trees soil is garden soil close to the main root ball (from years ago) and can't easily be removed without disrupting the main root ball. More high quality potting mixes were added throughout the years as larger pots were used. What do you mean by "flush out the root zone". It frequently gets a good drenching of water.

When I pruned all the dead branches I also repotted the tree with a fresh potting mix called "ferti-lome Ultimate Potting Mix". I was adviced by a local green house that it would work well.

For the last 2 1/2 years it has been in our living room with light from a patio window on the east and two other windows on the south side. Have had no problems in it's current location until about 6 months ago so I can't imagine that has anything to do with it. Goes outside on the deck during the summer, of course coming in before it gets too cold.

Hope this helps.
Nate

 

Well, I am no expert, but if the average life span of a commercially viable citrus tree went from 50 years down to 15 years as a result of disease... and we don't know for sure what ails yours, perhaps this scientific fact of life span reduction may be a part of your citrus's situation...Pierce's disease is rampant in parts of S. California...

Millet I believe, will better answer your query, regarding the root ball and flushing it, but essentially you will have to uproot the plant, shake off all soil matter, including what is compacted within the rootball...flushing it clean with 70F./21c. water...and repotting it in fresh coir mix potting medium...standby for her expert advice...

 

I think we will have to see some photos
of this tree to better determine if there
are more than a couple of problem areas.

The gummosis is not a good sign, need
to see where the gummosis is located
on the tree and how much growth is
affected. The blackened new growth
as the leaves are emerging is a sign
of a fungal disease, generally harbored
in the soil and then becomes airborne
later to infect new, emerging growth.

I am curious as to when you pruned
this tree, how close was it in time to
the six months of decline. Somehow
I think you may have had a Spider
mite infestation in the last year to
cause the leaf drop while the petiole
stays attached.

Flushing the root zone means to
give this tree a heavy watering to
force out salt buildup and other
impurities in the soil.

I am inclined to believe that this
tree is suffering some kind of
root imbalance as well. Either
perpetuated by some compaction
in the inner root ball, whereby
water penetration into the center
of the root ball is being impeded
or perhaps there has been a root
burn off in the past year.

I will have to do some checking
on the mentioned potting soil,
cannot make comment until
I know more about it and its
constituents but I can say
that fertilizer enhanced potting
soils can have a deleterious
affect on older Citrus in pots.
Better to give the old tree a
standard grade nursery potting
soil and then come in with some
liquid fertilizers at first until we
have forced out enough impurities
in the soil. The problem with
some of the enhanced soil
mediums for potted plants
is that at first the soil can
have a toxic effect on the
roots, which in turn really
slows down the rate of
any new growth to be seen
later. Yes, even leaf drop
with the leaves discoloring
and the falling off the tree
can be a commonly seen
sign that the roots have
been harmed. When I
see this happen on any
of my outdoor container
Citrus, I know the problem
is in the soil mixture in
that either I have forced
out too much oxygen with
continual hose watering
or the soil itself is toxic
to the tree and need to
pull the tree out of the
container, gently tap off
any loose soil around and
above the rootball, look at
the roots to see any signs
of root burn and give it a
new loosely packed in soil
and let my hose watering
do the packing of the soil
for me.

Was the tree a seedling
or was it a grafted or
budded form? When
was the last time you've
seen flowers on this tree,
either while being placed
outdoors or while the tree
was indoors? Is there
anything that you may
have done differently in
the last year to this tree
than has been done in
the past such as bringing
the tree indoors later than
usual, or holding back on
the amount of water while
the tree was indoors or
allowed more humidity
to reside in the home.
Do the leaves ever appear
to lose their gloss to the
leaves and seem to have
a dulled effect or perhaps
a dust covered look on the
surface of the leaves prior
to your bringing the tree
indoors for the Winter?

By the way, an upwards
curl to the leaves is an
indicator, that there has
not been enough water
given to this tree, rather
than a symptom seen
from too much water.

Jim

 

I’ve attached several photos to show the way the leaves curl and yellow prior to falling off – this entire process can take several months to occur. Also you can see the way some of the tiny new sprouts turn black, shrivel up and die, and I’ve included pics of the gummosis. It may be to little to late for this tree, I probably waited to long to get advice….as you can see she is complete denude of any leaves other than the lone sucker coming up from the base. I certainly don’t have a lot of citrus experience other than growing this tree from a seed taken out of a grapefruit I was eating for breakfast as a 4 year old. I’m way out of my league here in this forum surrounded by horticulture experts – but I do love to grow plants all the same. Perhaps I shouldn’t have done this but after months of decline I eventually just pruned all the dead looking branches off….as you’ll see she’s pretty bare.

So for some more history on this tree. I would say that the initial decline began around July (during which it was still inside because it was too heavy to move out onto the deck). After several attempts at fertilizing with miracle grow spikes and mixes it continued to decline until around September when I decided we should just try getting it more light and then moved it outside. It remained outside with no improvements and perhaps stayed out a bit too long as it started to get fairly cold at night. However, as I’ve described this tree was already in an apparent state of chronic decline at this point. We brought it in and tried more fertilizing, etc. 2 Weeks ago I pruned it back extensively leaving only the main trunks and getting rid of all the dead looking branches. Last week I repotted with the aforementioned potting soil. During the repotting several of the outer layers of the dirt fell off containing most of the finer root system. All that seemed to remain was the very inner core of large roots at the center. I'm guessing this is another really bad sign?

As far as flowering goes, I’ve never had any. From what I understand this is likely due to having it grown from a seed and the tree never reaching it’s preprogrammed height/leaf nodes. Is that correct? You mentioned changes this year compared to last – probably the biggest change was deciding not to break my back and move it outside in the spring……probably the wrong decision. Thought I had enough light from the patio window and the two south facing windows. I don’t think the tree has ever looked unglossy/dusty. You said that an upward curl of the leaves indicates a lack of water but we’ve been watering the heck out of it until just this last month. I keep checking the moisture about an inch deep into the soil and find that it is very moist, almost wet. I presume since there is no major uptake needs by the tree it is simply not using it quickly? So, I have not watered it now for about 4 weeks or so, I keep waiting for the soil to dry to the moisture level I've always used as the indicator for more water.

Thanks so much and I look forward to your response. Although I'm sure it would be easier to just grow another one from seed - it sure would mean a lot to be able to save this one - it's been with us now for so long it almost feels like family!!

Nate

 

I'm afraid I cannot help too much. All I can say is that the decorative pebbles on the soil surface may be doing some harm if they are affecting aeration/proper watering/evaporation etc

 

A few quick notes before I get
back to you on this tree.

Not all gummosis is caused
by a fungal pathogen such
as a Phytophthora gummosis.
Sometimes in Citrus we see
a bacterial form of gummosis,
essentially inbred into the tree
via propagation and can be
passed on from plant to plant
directly into the seed, after
the tree has experienced a
stress or a prolonged stress.

The new growth seems to be
all that you have to work with.
This is not good as the new
growth shows signs of salt
burn. Millet had the real
issue pegged all along
and that is your soil is
not helping you. As a
matter of fact the leaves
show almost a poisoning
effect from old and new
soil. You probably will
have to change the soil
for this tree soon or you
risk losing what little new
growth you have left. With
Sue's tree we had some
new shoots but they were
not able to grow and expand
due to a fungus but your new
growth is being adversely
affected from not enough
water to flush out the
insoluble salts and other,
some built up over time,
impurities from the old
and new soil.

You can try to salvage
this tree but it will require
a whole new starting over
process. Then it is up to
you to perform the various
work steps to help matters
and the trees will to respond
to those drastic measures.
All I did for Sue was to give
her a direction to follow if
she could. She did it and
the tree did start to come
out of its decline. For how
long and whether her
attempts to rescue the
tree worked - I have no
idea. I take no credit
for what I proposed she
do and did. She had
a choice of either trying
a new approach as a
series of last ditch efforts
or lose the tree rather
soon as it was. I would
hope the tree is still alive
but I am not aware that
it is or that it later
succumbed to the
elements. We may
get lucky and help
the tree along for
the near term but
there is always the
notion that after a
period of adjustment
that what was looking
like a slow recovery is
indeed a precursor to
the inevitable end. At
least we tried to help
when a successful
outcome may have
seemed hopeless at
one time or another.

This tree will require
some pruning, a soil
applied fungicide, a
changing of the soil,
a thorough leaching
of the insoluble salts
from the old soil, a
liquid form of fertilizer,
a marked increase in
the amount of available
light for this tree and
some crossing of our
fingers for luck. The
bottom line is that
whatever we do to
help this tree, it is
its will to live is what
ultimately determines
whether we have been
successful or not.

Jim

 

Jim, theoretically, it is "possible" for an indoor container grown seedling grapefruit to bloom and fruit, but personally I have never known of one to ever bear fruit. Further, over the years, I have never known any other citrus enthusiast, that I have come into contact with, that has seen a indoor containerized grapefruit ever become mature and produce fruit. Lazz knows a lady in South Carolina that grew a seedling container grapefruit indoors, for 15+- years with no results. The tree was finally planted outside in the ground and fruited 2-3 years later. As to your important point about the insufficient amount of light that the tree is receiving, I agree with you that the low light conditions are also having a deleterious effect on the tree's ability to bloom. However, the low light level is just another reason, that the tree is having a difficult time producing enough nodes to become mature. Even if such a tree did finally produce enough nodes, and did become mature, the tree would only produce fruit from that point on the tree and up. Also as the tree grows in size, the roots and foliage become greatly out of balance, so either the amount of foliage, or the extend of additional new growth suffers, or a larger and larger container has to be made available. All in all, grapefruit is just simply not a good variety of citrus to grow as a residential plant. - Millet (1,443-)

 

Thanks everyone,

I'll try to give it a good flushing and have already changed the soil. We'll see what we can do. Keep me posted if there is anything else I should try to do.

Nate