[binner]

a few of my sprouts and odd cabbage, plus some potato plants are showing signs of magnesium deficieny, i have just brung a couple of leaves home to compare in the book andi am 100 % sure. so, what now? it says spray them with a trace spray, but which kind/make/ brand etc?
also this is my first full year, last may it was a large patch of grazing land, so what should i do long term to up the levels of magnesium??? i dont seem to have any other problems at all, infact this week i have just cut some monster perfect cauliflowers they are hard to grow apparently :blink:

[Aunt Sally]

Epsom salts is what you could use binner.

Either a foliar feed or water on the roots.

[binner]

ok thanks for that

[daisy1990]

I have used Epsom Salts (buy from chemist very cheaply) I have added a tablespoon to a watering can full and watered on tomatoes etc.  They usually green up in a few days. I also understand that a feed that is nitrogen rich eg Tomato food etc will prevent magnesium being taken up by the plant if used in excess ie over feeding can cause the problem in the first instance

[Aunt Sally]

Thatis interesting Daisy.  Something new I've learnt today

[DavidT]

I didn`t know that either.

[binner]

thanks for the great quick help as usual,
just one thing, how do i stop it happening next year? i.e. what do i need to dig into the soil over the winter?

[Aunt Sally]

Compost and manure fixes most things

[binner]

ah thats good and simple then

[daisy1990]

I would agree nothing beats good well rotted manure and/or compost.  Have also tried the winter green compost (the greens that you sew over winter for the purpose of digging in in spring.)  It fed the soil well but looks messy!

[Aunt Sally]

I've sown alfalfa (lucerne) on part of my plot.  It is supposed to bring lots of minerals up from deep under ground.

[binner]

lots and lots of clay on my plot, needs plenty of work. i have around 10-12 in of workable half decent topsoil before i hit full on clay! i am well impressed with what we have so far though. two beds i started last year are doing very well, thay have been dug over twice and had lots of manure on them

[Aunt Sally]

Work some good stuff into clay and it can be very fertile.   It holds plenty of moisture and nutrients don't get washed out as easily as in lighter soils

[solway cropper]

binner, I see that live a long way from the coast but this year my toms, peppers, cukes have been fed entirely on home-made seaweed liquid feed and this is the first year they've shown not the slightest trace of Mg defficiency. Next time you have a day out in Bridlington fill the car up with seaweed 

[Salmo]

The older leaves of potatoes often start to look old now with either inter veinal yellowing or brown speckles due to magnesium defficiency. They will benefit from a watering with epsom salts. The speckles are sometimes confused with blight.