Good garden design starts with thinking before digging
Garden design takes time. It's too late to plan your garden when you are standing in the nursery eyeing every new plant that tempts you. Spend some time looking at your garden site, either during the offseason, when you can really view it objectively or during the growing season, when your successes and failures make themselves known.
Once you have an idea of how you are going to use your garden, come back to reality and take an objective look at the site before you come up with your garden design. This is of utmost importance in determining which plants and trees you use to achieve the desired effect.
Monitor it during different times of the day and year:
You know what you want to use your garden for, what you are working with and what resources you can devote to it. Now, what do you want it to look like?
Formal or informal? Wild?
Should it complement your house?
Do you want it to flow with the natural landscape?
Do you favor soft pastels or bold tropicals?
All these things might seem overwhelming, but you'll be saving yourself a lot of time and a considerable amount of money if you take this advice and you'll find that each step gets easier and more fun. Plant selection should be one of the last things you consider, or you may be overwhelmed trying to create a garden design to accommodate the dozens (or hundreds or even thousands) of plants you crave.
Plan ahead when planting bulbs; i.e., for spring flowering you plant in the Fall. Follow directions accompanying your bulbs regarding depth (usually six inches) and fertilizer (there are special bulb fertilizers that should be put in the planting holes). An important reminder - again: Know your planting zone before ordering any bulbs. They all look so beautiful in the catalogs, but what grows well in the midwest, in most instances, will not grow in South Florida! Special tools for planting bulbs are also available online. They make digging holes so much easier than using a simple trowel. Check them out.
Happy planting!