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I bought four Arabian Jasmine saplings from local nursery. I re-potted them into bigger pots. But then it looks like I made the criminal offense of the Jasmine world. I added NPK fertilizer granules and some Osmacot Rose granules too. Added some cow dung manure too. All into potting mix. I did add water too since I was re-potting them.The result is yellow leaves on two of the Jasmines. The one on the left in the picture below is one of them.

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Are these all doomed or will they pull through. I am keeping them in sun hoping that the roots dry out if this was a case of over watering. No more watering for a week at least.

Anything else I can do?

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Probably not doomed.

Cow dung, if not composted (i.e., aged) contains a lot of urine = urea. Even though urea is a potent nitrogen source, in higher quantities it reverses the osmotic balance and draws water out of the plant through the roots. This is known as fertilizer burn. The fertilizer granules add to this though they may take a bit longer to dissolve. Osmocote prills, on the other hand, release their contents slowly (over the span of months) and so aren't contributing to your problem.

It will help if you can scrape off all of the cow dung and fertilizer granules on the surface of the soil that you can. Then water repeatedly. Fill the pot to the top with water, let it drain, and repeat many times, lets say 10 times. Then wait two or three days and repeat if your plants are not already greening. You are trying to flush all that extra nitrogen salt from the soil. Once done, your roots will be able to adsorb water again and they will 'perk up'.

But, you are right. You committed a cardinal offense of gardening and horticulture in general, not just the world of Jasmines. What you need to understand is that plant roots take in mineral salts by an active biological process. This biological process needs to produce a higher concentration of the salt in the root cells than outside. If so, water then moves into the root cell by the chemical process of osmosis to balance the salt concentration inside the cell with the concentration on the outside (in the soil). Too much mineral salt on the outside makes water moves the other way, out of the root into the soil = 'fertilizer burn'.

It is very simple. A little fertilizer is a good thing. A lot of fertilizer is not.

  • Thanks for detailed reply. Will not watering too much to flush out nitrogen lead to root rot? – NotAgain says Reinstate Monica Mar 27 '16 at 1:59
  • It could, but that is the point of waiting a few days between flushings. If you don't give it any time to drain/dry the roots then begin to die for lack of oxygen (needed to burn sugars for those all important life processes). Once that has happened root rot can start. Over the span of less than an hour or so, roots can be submerged without causing a problem. – Jim Young Mar 27 '16 at 2:17

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