My aubergine plant seems to be developing some nutrient deficiency. I pulled it from the ground in autumn about 9 months ago and placed it into an air pruning pot with some potting mix, and kept it inside over winter. During this period it still flowered and produced several fruits which I consumed. The only issue were some spider mites which disappeared after spraying with neem oil.

I took it outside in spring after the last frosts, and it's started to flower again with fruits forming. I noticed a light aphid infestation today and sprayed with insecticidal soap. I've only fed it twice with a fish blood and bone mix, and general water with aquarium water.

I've noticed today that the older leaves are suffering with some interveinal yellowing, which seems to be starting from the middle and spreading out. Younger leaves are still green.

As aubergines go, this one is only 2 foot tall versus reaching the roof as with greenhouse grown plants.

Since the young leaves are not yet affected, is this more likely to be magnesium versus manganese or iron? pH is 7.4, and soil is moist.

the whole plant here young leaf older sick leaf

  • Graham...have you looked at this plant closely? I think it still has spider mite. There is no getting rid of spider mite once a plant gets it they will always be there. My first look at your plant told me spider mite and then you said it had had it. I don't see the webbing, you need to take your loupe and go look closely. Sure looks like spider mite is sucking the life out of your plant. If you can find a tub to make a batch of neem turn this guy upside down and DUNK it, swish it gently is the best way. Not permanent, however. Check the neighbor plants, too. This is spider mite!!
    – stormy
    Commented Dec 27, 2016 at 23:41
  • Spray your soil with neem and check the other plants. Dunk all of them that are in pots. Then tell me what fertilizers and how much how often you've used them.
    – stormy
    Commented Dec 27, 2016 at 23:42
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    Fish blood and bone, and aquarium water Commented Dec 28, 2016 at 0:53
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    Fertiliser i.imgur.com/Z5Df5Xo.jpg and npk i.imgur.com/isZ39li.jpg I saw these mites easily before. They're gone, and no webbing is present except for one ordinary spider web. Commented Dec 28, 2016 at 0:58
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    Actually aubergines grow in aquaponic systems which use fish poopy water. Commented Dec 28, 2016 at 2:11

2 Answers 2


First, I just noticed that you have 7.4 pH and that is a big no no for solanaceae. Too high for MOST plants. You need to get that plant into fresh potting soil. Normally potting soil is lower in pH. Takes a bit of time and work to lower pH UNLESS you are using potting soil. When you get fresh potting soil, test the pH with whatever you use, I use 3 different methods. 5.7 to 6.5...7.4 is very unusual. And you do have a stressed plant on a number of counts. First the spider mite which sure looks as if it is going strong. Being taken out of the garden soil and put in a pot and with the pH that high I can't comment on your fertilizer nor should you worry about fertilizer whether the chemicals are deficient or in excess. That pH has to be fixed first. Otherwise chemicals that plant needs that plant can not use until it is more acidic. That is way too high for alkaline loving plants such as lawns and marijuana!

Spider mite attack plants with much more success when a plant is stressed and weakened. And if you look closely at those leaves I'll put money down that you can see little spider mites and webbing and insect poop galore! To include white fly...I can see a bit.

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    I have pH about 7.3 (and subsoil to 7.8). Really not huge problems also for my aubergines. Maybe the vegetable garden is not so high in pH because of fertilisers (manure), but surelly not so low. I'll need to test. Only blueberries give me troubles (because of pH). Commented Dec 28, 2016 at 20:26
  • Spider mite damage doesn't start looking better for a long time...the new leaves look good, the others will not ever look healthy again. Even with high vigilance on the spider mite. The ruined leaves will fall off before they ever look healthy again.
    – stormy
    Commented Dec 29, 2016 at 21:53
  • The spider mite infestation was in July and treated at that time. These leaves are after that time. I'm wondering now if it's just aphid damage. Commented Jan 2, 2017 at 9:48
  • It is spider mite damage. Aphids aren't that big of a deal on leaves, perhaps buds, flower buds, flowers but they aren't a big deal sucking on leaves. This is spider mite damage. I've just been through hell with these things. Leaves do not recuperate. It is OK if you keep checking for live spider mite...when you get spider mite it is very apparent and there is no getting rid of it until you clean up the environment. Even then, one egg, one spider mite and the process starts again. Dunking is far superior to spraying.
    – stormy
    Commented Jan 2, 2017 at 21:18
  • I'm going to accept your answer as spraying for aphids has cleared the problem, and I can accept that there may be mites I can't see. Another pH meter says the potting mix is neutral. Commented Jan 15, 2017 at 1:20

To me, the yellowing on older leaves looks like plain old nitrogen deficiency.

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    Welcome to SE Gardening. This answer would be improved if you explained why nitrogen deficiency would these parts of the plant (hint: are they old or new leaves primarily affected?), whether or not Solanum melongena is particularly prone nitrogen deficiency and whether the particular cultivation method increases the likelihood of nitrogen deficiency. Commented Apr 20, 2017 at 21:24

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