Fertilizers need to be use in appropriate dose always because there excess use causes certain disadvantages which are as follows:

•Excess use of fertilizers affects the fertility of soil. They don’t allow any organic replenishment and also kills microorganisms present in soil which plays important role in improving fertility of soil. Due to this the fertility of soil gets reduced due to excessive use of fertilizers.

•Excess use of fertilizers is also responsible for water pollution. When excess fertilizers are supplied to the soils and excess irrigation is performed, the fertilizers get washed away and get accumulated in different water sources. By affecting the natural properties of water, fertilizers cause water pollution.

•Also, use of fertilizer is a kind of small term benefit as by affecting the fertility of soil it causes long term harm.

So, due to above mentioned reasons fertilizers always need to be use in specified amounts.