Definition of harden something off in English:

harden something off

  • Inure a plant to cold by gradually increasing its exposure to it.
    More example sentences
    • Add moisture retaining granules and slow release fertiliser to the compost and gradually harden the plants off before putting them outside completely at the end of the month.
    • Not everyone has the luxury of a greenhouse, but plants can be hardened off by taking them outdoors during the day and bringing them in again in the late evening.
    • Gradually harden them off over three to five days by putting them in a protected shady spot, first for half a day, then a full day, and then gradually into full sun.
See parent entry: harden

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Word of the day milord
Pronunciation: mɪˈlɔːd
noun
used to address an English nobleman