to hoe up the earth around plants
耔 centers on cultivating plants by hoeing or mounding soil around their bases to protect and nourish them.
耔 combines 耒 (a plow or farming tool) with 子, which likely contributes the sound and may suggest nurturing or tending, as in caring for young plants.
The left side 耒 is a farming tool, and the right side 子 looks like a child. Imagine using a hoe to carefully mound soil around a young plant, treating it like a child that needs protection.
For シ, picture a farmer hoeing the earth and saying 'She' needs good soil: She -> シ, as the farmer tends the plants.