Here is the full list of all 47 Viridi achievements. It takes around 15-20 hours to unlock all of the achievements on Windows.
Throw one hundred mature plants into the garden
Throw fifty mature plants into the garden
Throw ten mature plants into the garden
Flower a Sedum morganianum
Flower a Senecio rowleyanus
Flower a Aloe vera
Flower a Sempervivum
Flower a Lithops optica 'Rubra'
Flower a Aloe 'Blue Elf'
Grow a Sedum morganianum to maturity
Grow an Aloe vera to maturity
Flower a Pachyphytum fittkaui
Grow a Lithops optica 'Rubra' to maturity
Flower a Echeveria glauca
Throw one mature plant into the garden
Grow a Sempervivum to maturity
Grow a Pachyphytum fittkaui to maturity
Grow a Senecio rowleyanus to maturity
Flower a Pachyphytum oviferum
Grow an Aloe 'Blue Elf' to maturity
Flower a Haworthia attenuata
Flower a Fenestraria aurantiaca
Flower a Senecio serpens
Grow an Echeveria glauca to maturity
Flower a Kalanchoe thrysiflora
Flower a Pachyphytum glutinicaule
Flower a Pachyphytum hookeri
Flower a Sedum pachyphyllum
Flower a Echeveria runyonii
Flower a Cheiridopsis denticulata
Grow an Aeonium to maturity
Grow a Pachyphytum glutinicaule to maturity
Grow an Echeveria runyonii to maturity
Grow a Haworthia attenuata to maturity
Grow a Senecio serpens to maturity
Grow a Fenestraria aurantiaca to maturity
Grow a Pachyphytum oviferum to maturity
Grow a Cheiridopsis denticulata to maturity
Grow a Pachyphytum hookeri to maturity
Flower a Kalanchoe rotundifolia
Flower a Echeveria 'Lola'
Grow a Kalanchoe thrysiflora to maturity
Grow an Agave macroacantha to maturity
Grow an Agave 'Blue Glow' to maturity
Grow a Sedum pachyphyllum to maturity
Grow a Kalanchoe rotundifolia to maturity
Grow an Echeveria 'Lola' to maturity