Garden Size

Garden size does matter when it comes to flower beds and garden islands. If it's too big maintenance will become a problem. If its too small the plants could suffer.

This garden area was way too large.
It took hours to weed it.

It would take more plants to fill it than we wanted to purchase and even filled with plants it would have been hard to maintain. Standing on the slope to work was getting harder and harder the older I was getting!

So as much as I wanted this to be one huge garden area it had to be downsized to something more appropriate.

This is much better sized than before.

The planting area has been reduced to two of these boxes. There is still plenty of room for plants.

The beds are raised so they're easier to access. The back of the beds can be reached easily for maintenance.

Perennial Flower Borders

Flower borders are beautiful and fun to look at throughout the season. Something is always happening in them even when they aren't in bloom.

The general rules for flower borders widths are based on thirds:
1/3 the total space of lawn and proposed border area.
1/3 the estimated height of the tallest tree when placing beds against a forested area.
1/3 the height of a fence that backs it.

So if you have a total lawn and proposed flower border area that equals 30' wide you can have either a 10' wide flower border at one end of it or two 5' wide flower borders one on each end.
If putting the bed at the base of a 6' fence the bed would be 3' wide. This would seem rather small to me as I don't like to go less than 4' wide on border plantings. This is where the generality of the rule comes into play. Start out with a 3' layout mark and increase it to an amount that looks pleasing to you.

The final decision on garden size should always be made by you not the numbers. So play around with various sizes until you get one that fits your style and maintenace schedule.

Island Garden Size

Island beds don't have a horizontal backdrop that backs them.

They are typically kidney shaped and situated in lawn areas. While kidney shape is typical they can be round and any various form of curves. Square island beds create a formal feel. Free formed beds create casual feelings.

The general rule for perennial island flower bed sizing is:
2X as wide as the tallest plant in it.
3X as long as it is wide.
So a 6' wide bed should not have anything over 3' tall in it and would be 18' long.

These are general rules. If you plan on putting a 15' tall tree in the bed a 45' long flower garden might be too large for you. In that case you can use a garden hose to try various widths and shapes until you find on that works for you. Anything less than 6' wide will probably not work well in most situations involving island beds.

Terraced Garden Size

Terraced or tiered flower beds come in a few shapes often times curved but sometimes rectangular.

These are one of my favorites as they are bordered on all sides by brick, stone or wood. I can grow aggressive plants in them without too much worry about them getting out of hand.

The general rule for terraced gardens is no wider than 4 foot.
The length is generally no less than 4 foot long. You can go smaller but that won't leave much space for planting.

You need to be able to reach the back of the garden without having to kneel or step into it.

While there are rules to garden size you can always break those rules. Just keep maintenance in mind when chosing. Bigger flower beds require a lot more maintenance than smaller ones.

When you have your garden size figured out, you will want to read about color in the garden.

You might also enjoy these other garden design principles:
The purpose of your garden.
Create garden unity through repetition.
Create movement with garden color.
Texture in your garden.