Plantlet handling apparatus including: a housing for an aqueous liquid or aqueous gel nutrient medium; a plurality of plantlet holders each including a plurality of body portions forming, in assembly, an open-topped container having a tapering form from a top to a base portion, apertures open to said nutrient medium in use including a base aperture, and engagement means (103, 104) disposed between adjacent said body portions and engaging said body portions in assembly for handling; a plantlet holder support located in said housing and supporting said plurality of plantlet holders in said nutrient medium in use, characterized in that it further includes a closure for said housing having a substantially airtight seal to said housing and having selected permeability to metabolic gases produced or required by plantlets, wherein the plantlet holder has complementary halves, the base portions of the respective plantlet holder halves having respective engagement pins and holes which retain the two plantlet holder halves together along a partition line when the halves are closed together by bending about a self hinge crease, the plantlet holder when assembled having a pair of said apertures in one side disposed about the partition line, and a single large said aperture in the opposite side again disposed symmetrically about the partition line, there being provided a lug or projection on each said plantlet holder for handling the plantlet holder by manual or mechanical means, the closure comprising a polypropylene moulded body portion having formed in the upper surface a pair of windows formed in a raised portion, the upper surface being bounded by a peripheral stiffening ridge, the windows being closed off by a biaxially oriented polypropylene (BOPP) film heat sealed to the raised portion to provide said selected permeability. a housing for an aqueous liquid or aqueous gel nutrient medium; a plurality of plantlet holders each including a plurality of body portions forming, in assembly, an open-topped container having a tapering form from a top to a base portion, apertures open to said nutrient medium in use including a base aperture, and engagement means (103, 104) disposed between adjacent said body portions and engaging said body portions in assembly for handling; a plantlet holder support located in said housing and supporting said plurality of plantlet holders in said nutrient medium in use, characterized in that it further includes a closure for said housing having a substantially airtight seal to said housing and having selected permeability to metabolic gases produced or required by plantlets, wherein the plantlet holder has complementary halves, the base portions of the respective plantlet holder halves having respective engagement pins and holes which retain the two plantlet holder halves together along a partition line when the halves are closed together by bending about a self hinge crease, the plantlet holder when assembled having a pair of said apertures in one side disposed about the partition line, and a single large said aperture in the opposite side again disposed symmetrically about the partition line, there being provided a lug or projection on each said plantlet holder for handling the plantlet holder by manual or mechanical means, the closure comprising a polypropylene moulded body portion having formed in the upper surface a pair of windows formed in a raised portion, the upper surface being bounded by a peripheral stiffening ridge, the windows being closed off by a biaxially oriented polypropylene (BOPP) film heat sealed to the raised portion to provide said selected permeability.