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Zucchini blossom end rot

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David Hare-Scott

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Dec 1, 2009, 4:51:22 PM12/1/09
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My zuccs have BER! As I understand it the problem is due to deficiency of
calcium in the plant which can be brought about by uneven water availability
or lack of calcium in the soil. Well my zuccs have not been watered
unevenly, they have neither been saturated not allowed to wilt and they are
well mulched. The soil has been amended with lime and gypsum. They are
growing strongly with a multitude of flowers and fruit setting. One odd
thing is that normally this strikes on the fruit when they are quite small
but this time they are getting nearly to cutting size before it starts. As
a short term thing I am cutting them early which makes for nice tasty fruit
but a small harvest.

Any ideas from experience?

Any references to a detailed explanation of how BER happens, in particular
how uneven watering results in a mineral problem?

David

Bill who putters

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Dec 1, 2009, 6:00:39 PM12/1/09
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In article <hf4352$lef$1...@news.albasani.net>,
"David Hare-Scott" <sec...@nospam.com> wrote:


<http://urbanext.illinois.edu/search/searchresults.cfm?cx=013441887324743
351507%3Afnavtnakbe4&q=blossom+end+rot&sa=Search&cof=FORID%3A11&siteurl=u
rbanext.illinois.edu%2Fhortanswers%2Fdefault.cfm>

From above URL 4th hit down

"When the soil moisture experiences wide swigs in moisture (wet to dry)
that is when the plant has a hard time picking up calcium. To prevent
this condition you need to water so soil moistures stay fairly constant
or better yet use some type of mulch over the bed to even out soil
moisture levels. This is the best way to prevent blossom end rot. "

Bill

--
Garden in shade zone 5 S Jersey USA

FarmI

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Dec 1, 2009, 11:25:36 PM12/1/09
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"David Hare-Scott" <sec...@nospam.com> wrote in message
news:hf4352$lef$1...@news.albasani.net...

> My zuccs have BER! As I understand it the problem is due to deficiency of
> calcium in the plant which can be brought about by uneven water
> availability > or lack of calcium in the soil. Well my zuccs have not
> been watered unevenly, they have neither been saturated not allowed to
> wilt and they are well mulched. The soil has been amended with lime and
> gypsum.

Could there be a problem with water penetration due to the mulch? I know I
have to be quite careful of mulch on our low pressure, gravity fed, country
water supply and fluff the mulch every now and then or otherwise the
watering isnt' even.


David Hare-Scott

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Dec 2, 2009, 2:24:06 AM12/2/09
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I don't think so, the zuccs and other stuff in that bed are growing quickly
and not wilting on hot days so I reckon the water is good. But I will
insert the diagnostic finger more often to be sure. Thanks.

David

gunner

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Dec 2, 2009, 3:29:08 PM12/2/09
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"David Hare-Scott" wrote in message

>"My zuccs have BER!"

>"As I understand it the problem is due to deficiency of
calcium in the plant which can be brought about by uneven water availability

or lack of calcium in the soil.".

Absent more specifics, I believe that is more SWAG than fact.

Consider the chemical distribution of Ca w/in the plant.
Most likely your plant's available calcium is being diverted from the fruit
& going to the leaves where it is needed more at that particular time, say
for transpiration.

Ca is not a mobile nutrient, i.e. going where it is best needed. If BER
occurs when temps are high, try slowing the plant's transpiration rate to
get a better Ca distribution. Note, even if you have adequate soil Ca, its
uptake can be limited by other factors such as listed in the Spectrum
Analytic article* below . If BER is a constant problem, try the
preventive measure outlined in the ISHS abstract ** below.

>The soil has been amended with lime and gypsum.
> They are growing strongly with a multitude of flowers and fruit setting.
> One odd thing is that normally this strikes on the fruit when they are
> quite small but this time they are getting nearly to cutting size before
> it starts.

I'm curious; did a soil analysis/test indicate you needed the lime and
gypsum or is this just a gardening "best practice" method?

If you care to share; what type is your soil, pH, amendment regime,
fert/schedule, etc.?

> "Any ideas from experience?"
>
> "Any references to a detailed explanation of how BER happens..."

Try these:

* http://www.spectrumanalytic.com/support/library/ff/Ca_Basics.htm

** http://www.actahort.org/members/showpdf?booknrarnr=145_23

http://www.springerlink.com/content/ww87lw2086rj3v71/

http://jxb.oxfordjournals.org/cgi/content/abstract/44/2/509

General reads on BER:
http://pubs.caes.uga.edu/caespubs/horticulture/blossom-rot.html

http://wihort.uwex.edu/fruitveggies/TomatoDisorders.htm


David Hare-Scott

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Dec 2, 2009, 5:40:52 PM12/2/09
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gunner wrote:
> "David Hare-Scott" wrote in message
>
>> "My zuccs have BER!"
>
>> "As I understand it the problem is due to deficiency of
> calcium in the plant which can be brought about by uneven water
> availability or lack of calcium in the soil.".
>
> Absent more specifics, I believe that is more SWAG than fact.
>
> Consider the chemical distribution of Ca w/in the plant.
> Most likely your plant's available calcium is being diverted from the
> fruit & going to the leaves where it is needed more at that
> particular time, say for transpiration.
>

I am beginning to suspect that this is the case. We have had a rather warm
spring and these plants are putting on growth at a high rate.

> Ca is not a mobile nutrient, i.e. going where it is best needed. If
> BER occurs when temps are high, try slowing the plant's transpiration
> rate to get a better Ca distribution. Note, even if you have
> adequate soil Ca, its uptake can be limited by other factors such as
> listed in the Spectrum Analytic article* below . If BER is a
> constant problem, try the preventive measure outlined in the ISHS abstract
> ** below.
>
>> The soil has been amended with lime and gypsum.
>> They are growing strongly with a multitude of flowers and fruit
>> setting. One odd thing is that normally this strikes on the fruit
>> when they are quite small but this time they are getting nearly to
>> cutting size before it starts.
>
> I'm curious; did a soil analysis/test indicate you needed the lime and
> gypsum or is this just a gardening "best practice" method?
>

I have not had a soil analysis done as I don't see the need. I grow a very
wide range of fruits and veges quite successfully and I see no signs of
consistent problems which would lead me think the soil has deficiencies. I
have done pH tests myself using a dye indicator system which I believe to be
reliable and accurate enough for the purpose.

> If you care to share; what type is your soil, pH, amendment regime,
> fert/schedule, etc.?
>

The soil profile is about 20cm of nearly black silt over plastic smectite
clay (which I don't disturb). The silt is somewhat friable but has quite a
bit of clay and without amendment still clumps together to a degree when
wet. The starting pH is 5.5 and I have been bringing it up over time with
lime, it is about 6 to 6.5 now so I don't add lime as a rule now. When I
established the plot 4 years ago I added gypsum to help break up the clay.
I add chicken litter, horse manure, a touch of soluble potash and compost
every year and mulch with hay which gets incorporated. I add a seaweed
extract every two years. The citrus get a soluble trace element mix when
they need it. - about every three years.

The result is after 4 years the vege plot is much more friable and now has a
good infiltration rate, for a clay-based soil it is very good. Given the
clay and organic matter in the soil the TEC (and CEC) would be quite high
but I haven't measured it. I see no signs of nutrient runoff downhill.
There is no limestone or sodised soil around the area and the river water I
use to irrigate has an EC which varies with rainfall but is typically around
200-300 microsiemens/m. I use raised beds which gives drainage and about
40cm of depth.

The average annual rainfall is about 1100mm but the fall is extremely
erratic which is a potential problem. We have not had prolonged rain since
the summer veges were planted. However, the clay subsoil acts a sponge
soaking up water during rain and the releasing it in between times, to
illustrate, it is two months since we had significant rain, and five weeks
since anything useful in the rain gauge at all and in the last month we have
had record temperatures for the month up to 41C. Yet my pasture is green and
growing very strongly without irrigation. I have been monitoring the veges
and fruit trees and irrigating them as required.

So to summarise, I see no cause for calcium problems except the zuccs are
growing too fast for their own good.

thanks for the refs

David

Jonthe Fly

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Dec 3, 2009, 7:08:01 PM12/3/09
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David Hare-Scott

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Dec 3, 2009, 10:17:18 PM12/3/09
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Jonthe Fly wrote:
> hope this helps....
>
> http://www.nt.gov.au/d/Content/File/p/Plant_Pest/479.pdf

Thanks. None of the listed ways that insufficient calcium would be
available seem to apply. I may just continue cutting most of them small
(zucchini flowers are very "in" you know) and leave a few to grow, or not,
and await developments.

David

Jonthe Fly

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Dec 4, 2009, 1:14:37 AM12/4/09
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OK a longer check off list needs to be made it seems.
No heavy winds or sudden rain after a period of drought?


David Hare-Scott

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Dec 4, 2009, 6:25:41 AM12/4/09
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No, puzzling isn't it.

D

Jonthe Fly

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Dec 4, 2009, 7:42:12 AM12/4/09
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As you said you had record temperatures, could it be that these have
affected pollination at that crucial time.
I have the idea planted in the back of my mind somewhere, that
pollination stops when the temperature gets too high, and it may also be
that bees stop pollinating for the same reason....They slack off on hot
days....

Jonthe Fly

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Dec 4, 2009, 7:46:17 AM12/4/09
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I also found this, in the Net, which tends to give me the clue I was
looking for.. I suspect I'm right.

Q: I had a gardener ask me why the blossoms would suddenly fall off his
tomato plants. Can you explain that one? Also, why would cucumbers
suddenly quit blooming? (Mandan, N.D.)

A: One answer to both questions, high temperatures and a lack of
adequate moisture. While both like warm temperatures, the hot weather
we've been having and the lack of consistent rainfall will cause both
blossom abortion and non blooming. Even our zucchini plants are way down
on production this year and that's saying something!

David Hare-Scott

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Dec 4, 2009, 4:20:49 PM12/4/09
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This is true of some species such as tomatoes but I have not heard of it
regarding marrows. That doesn't mean that it isn't so.

David

Jonthe Fly

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Dec 4, 2009, 9:55:35 PM12/4/09
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Jonthe Fly

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Dec 5, 2009, 8:04:26 AM12/5/09
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Sorry I shouldnt have mentioned it.
Of course the nose is on your face.

Jonthe Fly

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Dec 5, 2009, 8:54:00 PM12/5/09
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Youre not easy to convince are you?

David Hare-Scott

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Dec 6, 2009, 1:21:27 AM12/6/09
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I do not rush into conclusions. I have grown zuccs right through summer
here for years, which is just as hot or hotter than the last month, and not
had the problem of BER. I think the prolonged flagellation of this
particular horse has just about reduced it to component molecules.

D

Jonthe Fly

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Dec 6, 2009, 2:46:46 AM12/6/09
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I always reckon if the others have been eliminated, whats left is the
answer. Have they been eliminated? Experience in servicing electronics
has taught me that. I would have thought the extreme hot weather would
have been the first thing to come to your mind. It does with me.
I reckon it could be climate change. Of course not living where youre
living, I wouldnt have known about the heat you were
experiencing.....But youve gone strangely quiet on this....
Never mind.

Wildbilly

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Dec 7, 2009, 12:02:54 AM12/7/09
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In article <GjJSm.60573$ze1....@news-server.bigpond.net.au>,
Jonthe Fly <e...@off.theworld.com> wrote:

The name is different, but the syntax is familiar. My, aren't you the
shy one.

Sooo, you've read Sherlock Holmes, eh? Well, bully for you. And then,
your mind just seems to just caved in.

I someone stood near you, which ocean would they hear?
--
�When you give food to the poor, they call you a saint. When you ask why the poor have no food, they call you a communist.�
-Archbishop Helder Camara

http://tinyurl.com/o63ruj
http://countercurrents.org/roberts020709.htm

desertgardener

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Dec 7, 2009, 12:26:11 AM12/7/09
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I live in the high desert where summer temperatures routinely head
into the 3 digits for days on end. I grow zucchini every year. I have
never had a problem with blossom end rot on zucchini, and I don't have
a drop in productivity during the heat waves. Corn and tomatoes don't
pollinate in the high temps...but zucchini, melons, cucumbers, peppers
are all fine.

cj

David Hare-Scott

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Dec 7, 2009, 9:35:06 PM12/7/09
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Wildbilly wrote:
> The name is different, but the syntax is familiar. My, aren't you the
> shy one.
>
> Sooo, you've read Sherlock Holmes, eh? Well, bully for you. And then,
> your mind just seems to just caved in.
>
> I someone stood near you, which ocean would they hear?

He appears to be posting from an Australian ISP. Who do you think it is?

David

gunner

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Dec 7, 2009, 10:50:13 PM12/7/09
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"David Hare-Scott" <sec...@nospam.com> wrote in message
news:hfke12$31o$1...@news.albasani.net...

My bet is on the Ghost of Christmas Past!


Wildbilly

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Dec 8, 2009, 1:10:19 AM12/8/09
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In article <hfke12$31o$1...@news.albasani.net>,
"David Hare-Scott" <sec...@nospam.com> wrote:

> Wildbilly wrote:
> > The name is different, but the syntax is familiar. My, aren't you the
> > shy one.
> >
> > Sooo, you've read Sherlock Holmes, eh? Well, bully for you. And then,
> > your mind just seems to just caved in.
> >

> > If someone stood near you, which ocean would they hear?


>
> He appears to be posting from an Australian ISP. Who do you think it is?
>
> David

That just means that we should have stepped on the eggs when we had a
chance. They're spreading.

Wildbilly

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Dec 8, 2009, 11:01:10 AM12/8/09
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In article
<wldbilly-589C3F...@c-61-68-245-199.per.connect.net.au>,
Wildbilly <wldbilly@without_a.net> wrote:

> In article <hfke12$31o$1...@news.albasani.net>,
> "David Hare-Scott" <sec...@nospam.com> wrote:
>
> > Wildbilly wrote:
> > > The name is different, but the syntax is familiar. My, aren't you the
> > > shy one.
> > >
> > > Sooo, you've read Sherlock Holmes, eh? Well, bully for you. And then,
> > > your mind just seems to just caved in.
> > >
> > > If someone stood near you, which ocean would they hear?
> >
> > He appears to be posting from an Australian ISP. Who do you think it is?
> >
> > David
>
> That just means that we should have stepped on the eggs when we had a
> chance. They're spreading.

What would stop an American from opening an ISP account in Australia?

gunner

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Dec 8, 2009, 1:30:23 PM12/8/09
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"Wildbilly" <wldbilly@without_a.net> wrote in message
news:wldbilly-5917C5...@c-61-68-245-199.per.connect.net.au...

> In article
> <wldbilly-589C3F...@c-61-68-245-199.per.connect.net.au>,
> Wildbilly <wldbilly@without_a.net> wrote:
>
>> In article <hfke12$31o$1...@news.albasani.net>,
>> "David Hare-Scott" <sec...@nospam.com> wrote:
>>
>> > Wildbilly wrote:
>> > > The name is different, but the syntax is familiar. My, aren't you the
>> > > shy one.
>> > >
>> > > Sooo, you've read Sherlock Holmes, eh? Well, bully for you. And then,
>> > > your mind just seems to just caved in.
>> > >
>> > > If someone stood near you, which ocean would they hear?
>> >
>> > He appears to be posting from an Australian ISP. Who do you think it
>> > is?
>> >
>> > David
>>
>> That just means that we should have stepped on the eggs when we had a
>> chance. They're spreading.
>
> What would stop an American from opening an ISP account in Australia?

In overstating the obvious... Well, did ya or not?

Back in July someone in CA was also confusing Blossom Drop and BER. hmmm.


John Savage

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Dec 15, 2009, 12:23:53 AM12/15/09
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Jonthe Fly <e...@off.theworld.com> writes:
>I have the idea planted in the back of my mind somewhere, that
>pollination stops when the temperature gets too high, and it may also be
>that bees stop pollinating for the same reason....They slack off on hot
>days....

Bees seem to be getting a poor rap here, and all of it undeserved. Allow
me to put in a word in their defence.

On hot summer days, flowering native trees hum loudly with the sound of
beating bees wings. The bees are working even harder in the hot weather!

If the number of bees you see in your garden falls off during heatwave
conditions, it's because those bees are needed back at the hive to fan
the brood (undeveloped bee lavae) in the comb and regulate the
temperature of the hive. Bees don't slack off in heatwave conditions,
they actually work harder than ever!

On the topic of zucchinis, as I have written here many times: the
beauty of growing zucchinis is that you DON'T NEED BEES because
zucchinis don't need pollination. Provided you harvest the fruit
within a day or two of its flower having opened, it doesn't matter
whether it has been visited by a bee or not.

Only if you want to grow a fruit to maturity do you need bees. But
allowing a zucchini to grow large means it loses its flavour, that's
why they need to be harvested while young and tender. In addition, not
allowing any of the fruit to grow for more than a few days keeps the
plant flowering vigorously and producing even more fruit, thus
improving the yield.
--
John Savage (my news address is not valid for email)

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