Tomato Plants Turning Yellow :(

Can anyone advice what may be causing this, and what I can do? Thanks.

 

Waterlogging can inibit mineral uptake and cause deficiency. The plants appear to be in flexi tubs, did you make sufficient drainage holes in the bottom?

 

They were planted in Tomorite compost and have been fed with tomorite too. Should they be fed more do you think?

Yes there are 6 holes about 1.5cm in diameter in each tub.

 

I was going to advise Epsom Salts too. finding me thread.

 

Epsom Salt

 

Thank you.

Thank you, will follow the advice and fingers crossed it helps

 

Epsom will only help if its a magnesium deficiency but looking at the plant i`d say its more likely overfeeding and overwatering. Mg doesnt affect the new growth, its a mobile element so the plant can move it from the older leaves, hence thats where symptoms show up first. The chlorosis/necrosis on the leaf edges suggests a calcium issue which is indicative of overwatering and/or overfeeding with a high PK fertiliser like tomorite when it is isnt required. The P and K overdose locks out calcium and iron which produce yellowing on the new growth as neither are mobile elements. Excessive K locks out Mg, in which case adding more Mg in the form of Epsom (magnesium sulphate) wont help. Soil PH will be out of balance as fertilisers are usually acidic. I would flush the compost with plain water and allow it to dry out a little before watering again. Put the tomorite in the cupboard until you see fruit appearing and then only feed at half strength.

 

thank you for such an informative post @Hex_2011

Any update, Alan? How are they now?