The energy of fall is cool and dry. You can feel it in the air and your lungs regardless of rain or snow. Coughs tend to be dry, even when there's phlegm stuck deep inside and is difficult to expectorate. Several approaches can remedy these coughs, if you can distinguish what sort of cough you have first.
A general technique, and one of the tastiest, for all types of dry coughs is to eat pears cooked with raw sugar. This moistens the lungs enough to help them expel the phlegm.
If this doesn't work, then the dry cough could be due to either Excess Heat, which dries the phlegm, or Yin Deficiency where there is minimal phlegm and its deficient heat dries what ever is there.
If the dry cough is from Excess Heat, try loquat leaf (Eriobotryae japonica), useful for both non-productive cough and viscous yellow sputum. It's fascinating when an herb has opposite functions like this, but loquat's neutral energy and ability to expectorate and direct Qi downward makes it useful for many cough conditions, including wheezing and asthma. It is often combined with fritillary bulb in a cough syrup.
Speaking of cough syrups, they are a good way to moisten the lungs and help expectoration of non-productive phlegm. There are many good ones on the market but hands down the best is Old Indian Cough Syrup, useful for many different types of coughs.
If the dry cough is from Yin Deficiency, then try marshmallow combined with wild cherry bark and mullein. Again, syrup form is probably best in this case to add more moistening qualities to the formula.
If that doesn't work, use ophiopogon. If you've been following my blogs then you'll remember that I wrote about this single herb back in March 2009. To summarize it here, ophiopogon is sweet, cooling and moistening, nourishes Yin and clears Deficient Heat while at the same time expectorating phlegm from the lungs. It is in the formula Ophiopogon Combination, which treats flushed face, dry and irritated throat, spasmodic coughing, hoarseness, and dry mouth regardless of whether it presents as dry cough, bronchitis, tuberculosis, diabetes, hypertension, hoarseness, pneumonia, asthma, or laryngitis.
Ophiopogon (mai men dong)
Pinellia (ban xia)
Ginseng (ren shen)
Rice (jing mi)
Licorice (gan cao)
Jujube dates (da zao)
Treats: nausea, vomiting, thirst, dry throat, mouth and skin, dry, non-productive cough, spitting of saliva, dry mouth and throat, hiccups, five palm heat, red tongue with no coat and a weak and rapid pulse.