also: ほんよう
noun
true leaf; foliage leaf
Botanical term for the leaves that develop after the cotyledons (seed leaves). Used in gardening and plant science.
双葉が出たあと、本葉が何枚か出てきた。
After the cotyledons appeared, several true leaves came out.
本葉が展開し始めたら、間引きをします。
When the true leaves start to unfold, thin the seedlings.
双葉 refers to the cotyledons (seed leaves), while 本葉 refers to the true leaves that grow afterward.
Compound of 本 (ほん, 'true' or 'main') and 葉 (は, 'leaf'), with rendaku voicing to ば. The reading ほんよう is a less common on'yomi variant.