Answer
How do I plan a garden from scratch?
Start with use and a survey, then a design, then build structure-first. Not plants first.
In short
Start with how you want to use it and a proper survey, not with plants or products. From there comes a design that resolves the layout, levels, materials and planting as one scheme, which is then built in a sensible order, structure first. Planning it properly first is what avoids expensive changes later.
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