What it says: Do not disturb. Tiny grass is dreaming.
What it should say: Stay off the grass (?)
The Chinese is actually untranslatable. It is likely that the person doing the translation actually started with English and attempted to translate back into Chinese because neither 休扈 nor 扛搅 actually mean anything - they definitely don't mean 'dreaming' which is the cute part of this picture.
For the first error, I suspect that the sign-writer was somehow confused by the homophonous expression xiūhù 修护 ("under repair / maintenance"). It would have been more natural to say that the tiny grass is xiūxī 休息 ("resting") or, to match English "dream" in what I suspect might have been the impetus for the wording, zuòmèng 做梦 ("is dreaming"), mèngxiǎng 梦想 ("dream"), or some other poetic expression for "dream" containing mèng 梦.
The second error is probably orthographic, since it would be perfectly acceptable to write dǎjiǎo 打搅 ("disturb") in that position. When written hurriedly and sloppily, dǎ 打 and káng 扛 resemble each other. It would also be perfectly acceptable to write dǎrǎo 打扰 ("disturb"). The fact that dǎrǎo 打扰 ("disturb") and dǎjiǎo 打搅 ("disturb") are synonyms and sound similar may also have contributed to the confusion.