Dear Aparna
First of all collect the monthwise factual data about the quantity of Tea manufactured, Quality of Tea Manufactured, No of workers engaged, Quantity of Tea sent to market, Quantity of Tea received from Factory, Sales data of each month, alongwith the complete programme schedule of the Boss and submit the same to your boss for analysing the subject. You can give your opinion to your boss politely without any complaint, that in his absence period the production is going down and similarly the sales are also going down.
If you analyse and take forward this issue in this way this will surely useful for your company as well as the management and the management will feel that deploying the HR is not waste and it will surely fetch good productivity to the organisation.
Wish you all the best