Bitter Pip in Apples

[patricil1508]

Having read that this was caused by "lack of Calcium"  we thought we might introduce some Chempak Calcium into the soil.  However, during a radio gardening phone-in this morning, the advice given from an organic gardener was that introducing more calcium into the soil would not necessarily work as more often than not the calcium is locked into the soil as a result of the use of own compost mulches particularly on cooking apples.  We have been using own compost and grass clippings to mulch fruit trees.

Other members experience/knowledge on this subject would be so welcome - our cooking apple crop (Lord Derby) was ruined last year.

We also feed with potash in February each year.
and try to keep trees well watered in season.

[patricil1508]

[Palustris]

From my reading about this I would agree with the phone in answer. Calcium is not easily taken up by the apple trees and  extra added to the soil may not be taken up. The other point that my books make is that calcium deficiency is associated with certain weather conditions. Drought is one of them and where there are wide fluctuations in temperature, like last year perhaps. It is also more likely to occur on strongly growing young trees overfed with nitrogenous material, like grass cuttings. It is also associated with too high levels of potassium and/or magnesium.
The cure is reputed to be difficult, spray with calcium nitrate (if you can buy it) and/or keep the trees well watered in drought conditions.
We will just have to hope next season is better.

[patricil1508]

Thankyou Palustris, we will certainly try to get some calcium nitrate this year, and have a word with the Weather Fairy.

[john_miller]

Another problem you may be producing is that in plant nutrition K is regarded as an antagonistic ion (which basically means that it will knock off nutrients from their holding sites on soil particles and cause then to be washed out of the soil). The first ion it will cause precipitation of is calcium I would suggest you do a soil test around your apple tree to see if you haven't added to much K.

[patricil1508]

Hi John
Thanks again - we did have the soil tested recently but this did not seem to be a problem - perhaps its back to calcium nitrate spray or the Weather Fairy!

[tim]

BTW - bitter pit - not that it makes it any better. Even the Farmer's Market Bramleys had it last year. As we did. Put photos on the board. And the water shortage does seem to be the prime cause.

[patricil1508]

Thanks Tim (hubby always said I can't spell, of even type) now hes got even more ammunition.
Sorry I missed your posting last year, but it seems we are at least in good company albeit without apple pie.

[Kerry]

i posted this in answer to Tim's bramley question a while back-here it is, to add to your answers above....
in 3 lots so it's not too long a post to read!!


"searched my pests diseases and disorders book- suggest it is calcium deficiency-matches the description and pictures of your apple.
here's what mr buczacki et al has to say: i'll post in 3 parts as even abridged it's looong!

calcium deficiency symptoms occur most commonly in plants growing on acid peats, on acid soils originating from rocks with a low calcium content (granitic types and silicic sandstone) symptoms also occur on light free draining and easily leached sandy soils.
plants commonly affected include apples.
it is probably rare for there to be a true deficincy of calcium in the soil, the effects most probably being induced by an imbalance of calcium with other elements, or an interfering environmental factor.   next............"

[Kerry]

" symptoms:
when foliar symptoms occur they are most common at young leaf or shoot tips, which may be curled inward or ragged, scorched and killed.
apple: fruit, the most common symptom is bitter pit, dark spots or pits on the surface with brownish spots beneath and also scattered throughout the flesh-bramley's seedling is highly prone (but you know that!). other symptoms on apples include glassiness, lenticel spotting  and death of fruit tissues when stored under low temperatures.

physiology:calcium is relatively immobile in tissues, not moving readily from old to new leaves, which therefore display the 'starved' symptoms. it's a vital component of cell walls, essential for functioning of growing points and root growth.
excess potassium, magnesium and ammonium-nitrogen in the soil decrease the availability of calcium to plants. other limiting factors of availability are water stress and high humidity.
nearly there........."

[Kerry]

"treatment: not easy because of the inter-relationship with other factors. in acid soils, add lime to raise pH to 6.5, although this will not help on sites where calcium is not deficient, but unavailable to the plant. book suggests using pH meter to test the soil.
calcium deficiency is also minimised by reducing applications of potash and ammonium, while symptoms in apples can sometimes be cured by spraying the affected fruit (not the plant) at fortnightly intervals with solutions of calcium nitrate or calcium chloride containing approx. 2g per litre.

i checked the rhs site also-they reckon inadequate water is the culprit-so calcium cannot be effectively transported around the plant. they recommend mulching and watering, and summer pruning."

[Agnes]

Kerry, thankyou for such a comprehensive summary of this problem with possible solutions.

In the light of all the information I've received it seems very likely that last summers spasmodic rainfall (especially here in the south-east) was the main contributing factor, but I will watch the potash levels!!
Who knows, there may yet be apple pie next autumn.(Yum)

[loz]

Just as an aside, I put your question to a colleague of mine who is something of an expert in the fruit tree field.  He agreed that while calcium uptake is the major cause, many newly planted trees can suffer from the complaint for up to three years while the root system gets established.

By improving growing conditions you will encourage a good root system which in turn should take up more calcium.

Strangely he mentioned that short term treatments are unlikely to be very effective

Loz