1. The roof pieces will keep out rain and snow, but plants may still go dormant in winter.
2. Some have said that you can leave out one wall section, plant things, then add in that section.
3. The swiftgro station will water planters, but sprinklers will not.
4. The swiftgro station can be used indoors or outdoors. It has an option to open the composter and add 3 pieces of fertilizer. After that you can choose to fertilize all plants under the station. If that fertilizer is the sunshine from a dancing sunflower, it will also weed the plants. The station will also cause plants to "age up" twice a day, giving you 2 harvests but you also have to weed twice. You can use the station to identify unknown seeds, but separate the seeds first. If you have them all in the same stack and they turn out to be different types of seeds after identifying them, the game will error. You'll loose all but 1 seed in the stack.