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The leaves on all my garden herbs (mint, sage, oregano, thyme, lemon balm) get yellow-brown speckles from late spring, which by late summer almost entirely cover the leaves.

What might this disease (or diseases - the mint looks like rust but I've not heard of rust affecting thyme) be, and how can I treat it? And can I still eat the affected leaves?

Mint Oregano Thyme plant sage plant

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    Have you checked the underside of the leaves for spider mites? And are your plants in pots (what kind of growing medium?) or in open garden soil? Does that pattern of disease occur annually? – Stephie Aug 19 '17 at 20:13
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    Oh, and of course: Welcome to Gardening & Landscaping SE! Even for seasoned SE users like you, browsing the help center can be interesting. If you need personal help, you might pop into Gardening & Landscaping Chat, see who's hanging out there or leave a message. – Stephie Aug 19 '17 at 20:18
  • This is an example where learning to make beds for plants is crucial. These plants are competing with weeds for chemicals with which to make food and energy. Thus they are weak and susceptible to everything that want to use them for energy. Spider mite looks like a possibility. But that isn't what the problem for these plants is...you need to learn to make plant beds... – stormy Aug 19 '17 at 21:45
  • It is annual (3 years so far). The mint, lemon balm and sage are in the ground; the oregano and thyme are in an old pot sink (half and half compost and garden soil) – aucuparia Aug 20 '17 at 16:19
  • No sign of spider mites that I can see; however there are some tiny (1-2mm) insects that look a bit like miniature grasshoppers and which jump and fly around if disturbed – aucuparia Aug 20 '17 at 16:26

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