Gardening Question

If you make a little garden by using the lowest wall in a 10 x 10 size, will the Sims be able to plant/weed/water all the plants even if there isn't an opening or do I need to have an opening, walkway, and space between all the plants for my sim to walk and do the tasks?

I suppose I could put sprinklers all over the little garden for watering... hm. But that wouldn't help with weeding, planting, evolving, or harvesting.

Does the hireable gardener harvest anything?