使耐寒以备室外种植 become hard, ready for planting outside
harden off
When the onion plants have hardened off, we can plant them in the garden; they should be ready soon.
洋葱苗长壮后,我们就可以把它们移植到菜园里; 这些苗很快就可以移植。
harden sth ⇔ off
What is the best way to harden off new rose bushes only a few inches high?
要想使只有几英寸高的玫瑰长壮以移植户外,什么办法最好?
Potted plants should be hardened off before planting out.
盆栽植物应经耐寒锻炼才能移植到室外。