By Ellataylor
United Kingdom 
What causes plants to go 'blind'? This has happened to my Cosmos grown from seed and otherwise very healthy.
19 Jul, 2016
Answers
If they are in containers, intermittent drought could cause the buds to abort while young. Less common in the ground, since they develop deep roots for an annual.
19 Jul, 2016
Too much nitrogen fertilizer & insufficient sun are two common reasons. More information is needed to give an exact diagnosis.
19 Jul, 2016