If you haven't yet fed your cabbage with fertilizer to help it form heads, now is the time to do so.
We will tell you what fertilizers to use for feeding cabbage at the end of July.
How to feed cabbage to form heads
Cabbage needs potassium and phosphorus to form heads.
Also in the second half of July, cabbage still needs nitrogen for leaf growth.
The first option is to water the cabbage with a solution of mullein (a liter of fertilizer per 10 liters of water), and after 2 days with a solution of potassium monophosphate (a tablespoon per 10 liters of water).
Secondly, you can add a mixture of potassium chloride, ammonium nitrate and superphosphate (8, 10 and 15 grams per 10 liters of water, respectively)
You can also use a complex fertilizer with nitrogen, potassium and phosphorus, for example, nitroammophoska (10 grams per 10 liters of water).
