bud, sprout, spear, germ
芽 centers on the early stage of plant growth: a bud, sprout, or germ. The spear sense is a narrow application referring to a pointed young shoot.
芽 combines 艹 (grass/plant) with 牙, which likely contributes the sound and may suggest a pointed shape like a tusk or tooth, fitting the image of a sprout breaking through.
The plant top 艹 sits above 牙, which looks like a tusk poking up. Picture a tiny sprout pushing through the soil like a sharp tusk emerging.
For ガ, imagine a gardener gasping with delight when the first bud appears: gasp -> ガ, and the sprout breaks through the ground.
sprout; shoot; bud
bud; sprout
germination; sprouting; budding
to bud; to sprout
malt
sprout; bud; shoot
germination; germ; sprout
to bud
flower bud
leaf bud
gemmation
granulation; granulation tissue; proud flesh
Brussels sprout (Brassica oleracea var. gemmifera)
bud; sprout; shoot
germ (of a cereal, e.g. wheat, rice); embryo bud
spore
winter bud
Wegener's granulomatosis; Wegener granulomatosis
ameloblast; tooth enamel depositing cell
caramel malt