Don’s Expert Answers: Nutrition & Irrigation

Question From:
Andy in Pakenham, Melbourne Victoria

Nature of problem:
Nutrition & Irrigation

Type of Plant (if known):
Meyer Lemon

Symptoms of Plant Illness (please try NOT to diagnose your problems yourself):
yellow leaves, leaves dropping

Soil Type (e.g. sandy, clay or loam) OR Potting Mix Type:
clay pH 5-6

How often do you water the plant:
daily 15 minutes

How many hours of sunlight does the plant get each day:
full sun

How long since you planted it:
not sure, came with the house

Have you fertilised? If so, with what and when:
Richpro Mega Booster about 600g over 2×2 or 4m2, 2 months ago 17 sept

Is the plant indoors or outdoors:

Is the plant in a pot or in the ground:
in ground

What other treatments have you given the plant:
iron chelate 20mL in 4L water, seasol seaweed emulsion 100mL in 5L water, gypsum few handfuls, 2 bags of mushroom compost, grass clippings, epsom salt 80ml in 8L water

Upload photo if available:

Other Comments:
Good afternoon Don,

First of all, thank you for your wonderful knowledge sharing.

Please find the images i uploaded via Imgur

Can I ask the below questions (I’ve searched throughout the previous questions asked by others but I can’t find ones that has symptoms similar to mine)

1) is my lemon tree has magnesium deficiency? judging on the V shape green base at the leave. But some of the leaves are yellow throughout, eventually turns brown and drop. Is there anything I can do?
i follow your advice of adding epsom salt but when you said 2 teaspoon of epsom salt per 1 litre of water, do I have to apply to all the water that day or just do one watering can of 8-9L?

2) I accidentally left the garden tap which connect to the tree irrigation system on for 10 hours last night from 7-6am. This morning I had a quick check and the ground doesnt seem to be soggy (although it’s clay). Is there anything I should do to the tree or just leave it and water again after 2 weeks?
Can I please confirm the correct method to water lemon tree ? would it be over long hours in every 2-4 weeks?

Thanks again and look forward to hearing from you soon!

Hi Andy, Thanks for the kind comments and the brilliant photo. Yes it is Magnesium deficiency. If you switch to Osmocote liquid citrus fertiliser in August and February, all should be OK since it contains magnesium. Stop using all other fertilisers and the iron chelates etc as this is throwing the balance of elements off, hence the magnesium deficiency. Also treat it with Yates Anti rot in case it has root rot. Water it once a week for 15 minutes. Good luck, Don