Tomato Prob.

[telboy]

Hi All,
I was checking my toms. yesterday & noticed that three fruits on one plant had 'black bottoms' & rotting. No sign of blight on any leaves. Picked 'em off & ditched them.
Any ideas?

[telboy]

[Vez1]

Blossom end rot, comes from irregular watering.

[Curryandchips]

Yes, blossom end rot. It seems extremely common with this hot weather, even the seasoned gardeners round our way are finding it. The tomatoes can still be eaten, well the good half anyway.

[Robert_Brenchley]

A few of my outdoor toms have it, and they taste OK. In a damper atmosphere, the rot might be more active, and the end less palatable!

[Tee Gee]

Each year this problem comes up and I wondered; apart from the usual answer ' irregular watering' has anyone tried to resolve it?

Like many of you I get it occasionally yet I water every day if necessary.

There are some that would advocate you should water more than once a day when conditions are like this.

My thought relate to the root system i.e. the upper roots are 'feeding roots' whereas the lower roots are 'water seeking' roots.

This makes me think it is only partially a watering problem simply because, the 'water seeking' roots may well have plenty of moisture.

Which brings me to the 'feeding roots; these are sometimes laid bare due watering the soil off them and exposing them to light.

But worse still they dry out meaning the plant is not getting its full complement of nutrients to keep it in the best of health, the result being problems such as 'blossom end rot' and I suppose magnesium defficiency could be attributed to this i.e. not that isn't any magnesium about its just the plant can't take it up because the feeding roots are dry.

Even if they are not laid the soil surface may dry out quite rapidly which once again will reduce the moisture availablity to the feeding roots.

Is the answer to mulch the tomatoes or grow them through black plastic sheeting?

Your thought would be appreciated.

[supersprout]

The explanation sounds wizard teegee.
I mulched my outdoor toms heavily and didn't water - no BER.
My neighbour waters and doesn't mulch - he has awful BER.
I water my g'house toms and don't mulch - some BER.
I know what I'll be doing next year - and will mulch with fresh comfrey leaves as well as leaves and straw after reading your post, as these should give some useful nutrients for the 'feeding roots' :D

[Curryandchips]

Blossom end rot is actually the result of lack of calcium, if I recall correctly (and I willl willingly be corrected on this) although irregular watering is the most common method by which it occurs.

http://pubs.caes.uga.edu/caespubs/horticulture/blossom-rot.html

[tim]

Calcium, MrG?? (later - you beat me to it, Curry!)

I have to say that, since I went onto deep bags, where very little root is laid bare, my BER incidence has diminished.

Watering? Always regular - since I live here - &, as said before, 3 times a day in the heat.

[Hyacinth]

The link in my files is similar to Derek's, tho from N.Carolina & comes to the same conclusions.

In the g.house, I've always in previous years watered/fed regularly & top-dressed with superb w/rotted thickly, & never had this prob.

This year? General neglect has brought this problem on. But toms in the open ground have fared better with equal neglect.

[tricia]

My outdoor toms (Harbinger, Harzfeuer,New Yorker,Dombito) are variously laden with fruit. I water each plant through 2 liter coke bottles half buried and angled to the roots. They get watered every other day or so and fed twice a week with Tomorite. All are thickly mulched with dried grass (more like hay). So far I have found just one green tomato on a Harbinger plant with signs of BER.

The GH varieties are Harzfeuer, New Yorker and Dombito. The New Yorker lost its growing point but has produced a good side shoot, so I may still get a couple more trusses. A week ago I mulched these with used potato sack compost after noticing the fine white roots had appeared. So far, here too, only one green tomato with BER - on the Harzfeuer.

I'm glad I was put right as to the the causes of BER. My information was flawed and I now know that if it is caught early enough only a few fruit are lost.

I also have 3 Costoluto Fiorentino in pots outside on my south facing patio which have each set just one heavily laden truss and a meagre second. Weird - as they get the same treatment as all the others.

Tricia

[Hyacinth]

SNAP Tricia! I'd two C.F's , both in pots (and therefore suffering dreadfully but equally from my over-the-board neglect, ) & I've cut them back to leave only the 1st truss (laden) on each remaining,  to hopefully grow them on to fruition? I don't know, obviously, but I believe that if these two had been planted in the open ground they would have survived my neglect better?  I'm laying the blame firmly at my  feet on the poor showing of these.

[Robert_Brenchley]

My outdoor toms have been left unwatered until the last few days, since they started showing signs of wilt. I've had a little BER, and they stopped flowering a while back, but apart from that, no problems.

[tim]

Strange that, Lishka - yes, one would expect the soil-based ones to be more stable but, in a drought year, I would have thought that they might have fared less well?

[Tee Gee]

Yes Tim I agree about the calcium intake you mention.

But I was referring to any form of mineral uptake i.e. if the roots are dry they can't take up any form of nutrient, if uncovered but moist they can take up some nutrients but not enough hence the deficiencies, however fully covered and moist there invariably is no problem.

The other postings seem to confirm this or something along that line.

But as I said before it was just a thought and all the replies were appreciated.

[tim]

So right!

[Curryandchips]

Well I picked about two dozen tomatoes earlier, half of them with BER, but after careful paring in the kitchen, they have all gone to create a panful of ratatouille ... I will report on the final result later ...

[tim]

Strangely, it's mainly Santa that has BER this year.

[telboy]

Thank you all for your informative replies.
I now know what to do!