种草 (zhong cao) is a popular internet slang
It is commonly used as a verb. It generally refers to the act of promoting the superior quality of a certain commodity, in order to attract people to buy it.
With the advert of social media such as Weibo and Facebook, it is also generally referred to as recommending the same thing to another person, letting another person like it. It refers precisely to the process of this happening.
For example:
"种草一下最近买到的这款礼物包装纸，质感很棒，有纹路，摸起来很舒服！"
(Zhǒng cǎo yīxià zuìjìn mǎi dào de zhè kuǎn lǐwù bāozhuāng zhǐ, zhìgǎn hěn bàng, yǒu wénlù, mō qǐlái hěn shūfú!)
"Here to promote this wrapping paper that I recently brought, the quality is amazing, has great texture and is very comfortable upon touching it!"
Interesting, if you take it for its literal meaning, 种草 just means planting grass. Aren't the Chinese creative?