The greenhouse is a blessing. You might wana start crafting quality sprinklers for it in advance tho since they need a setup of 24 quality sprinklers. If you unlock the sewers buy iridium sprinklers from Krobus too.
Quality sprinklers require having reached down to at least floor 80 in the mines though. And for someone who's short on money, it's way more worth it to reach the bottom of the mines, unlock the bus, and mine the iridium needed for the iridium sprinklers from the Skull Cavern. The total of 42,500 G for the bus is more value for money than buying 1 iridium sprinkler at 10,000 G once a week for 6 weeks in a row.
