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Re: Dark Spot at Bottom of Tomatoes

Hi Bob,

> Greetings From Sunset Zone 23 in Swinging So. Cal!

> This is my second year of growing tomatoes. I had pretty good success last
> year, but now all my tomatoes are developing large dark spots on the bottom
> as they approach full size. What is up with that? Anything I can do—beside
> cut the bottoms off all my tomaters before I eat 'em?

> Also, my ripening tomatoes are cracking, which I understand is from
> overwatering. Several of my plants always seem to have wilting leaves, so
> I've assumed they need more water. Could something else be the cause of the
> wilted appearance?

> Bob Clemente
> Whittier

Both the black spots, known as blossom end rot, and the cracking are symptoms of
uneven watering.  Blossom end rot is caused by a lack of water in the soil,
which limits the calcium uptake by the roots, causing the problem, AFAIK. 
Cracking occurs when the plants get a good watering after a dry spell, the fruit
swells up faster than it's skin can accommodate, causing the cracking.

The solution is to water more often, so the soil stays more evenly moist.  Drip
irrigation and an automatic water timer is the way to go in an arid climate,
IMHO.  I grow tomatoes under cover, which creates a very arid microclimate and
use a seeping hose and timer to water my plants every other day.  You could
water a small amount every day for that matter.  If you only have a few plants
and the time, hand watering will suffice.  If you have more the value of having
a timer and irrigation system becomes apparent!  Having the bed well mulched to
prevent excessive evaportion also helps to even out the soil moisture.

Regarding wilting, it may be just a lack of water.  It is best to water early in
the day before the heat kicks in.  This way the plants will have had some time
to take up the moisture they need to deal with the building heat.  Wilting can
sometimes occur because of a dramatic change in temperature, even though there
is sufficient moisture present.  For example, in my garden I have some tomatoes
that don't get any direct sun until about 11am and then WHAM, the full sun bears
down on them.  They have a tendency to wilt under these conditions, even when
the soil is moist.

Hope this helps.

Cheers!

--
 Bob Carter  -  bcarter@awinc.com
 Kootenay Bay, BC, Canada  -  Zone 6b
--

... All progress stems from change but all change is not necessarily progress.

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