Balcony Garden Planning: How to Map a Small Space

A small balcony punishes impulse buying. One pot too many and the door will not open fully, or the only chair has nowhere to go. Half an hour of balcony garden planning with a tape measure and a pencil prevents most of that.

The method below produces a simple scaled sketch of your floor, with the fixed features, the light and the wind marked on it. From there, placing furniture and containers is a matter of moving shapes around on paper instead of carrying them around in real life.

Step 1: Measure and draw the floor to scale

1. Measure the length and the width of the floor. If the balcony is not a plain rectangle, measure each side.
2. Pick a scale that fits your paper. On graph paper, one square for every 6 in (15 cm) works for most small balconies.
3. Draw the outline. Label which edge is the wall of the building and which edges are railing.
4. Write the real measurements along each side so you do not have to convert back later.

Step 2: Mark what cannot move

Add every fixed feature to the sketch before you think about plants.

• The door and its swing. Draw the arc the door makes as it opens, or the sliding panel’s full opening. Nothing goes inside that arc.
• The drain or scupper. Mark where water leaves the floor. It must stay uncovered.
• An outdoor tap or outlet, if you have one, and any vent, light fitting or air-conditioning unit.
• The walking path. Draw a clear route from the door to the place you will sit and to the railing. Allow enough width to walk through carrying a watering can.

What remains after these are drawn is your usable space, and it is often smaller than expected.

Step 3: Add the light and the wind

Now layer on what you know about conditions. If you have not yet counted the hours of direct sun, do the one-day check described in the guide to measuring balcony sunlight and bring the results back to the sketch.

• Shade the zones that get about six hours or more of direct sun in one color.
• Shade the zones that get less than about three hours in the other color. Leave the in-between areas plain.
• Mark the windy corner with an arrow showing where the wind usually comes from, and circle the calmest corner.

If wind is a regular problem, the guide to assessing a windy balcony explains how to find those corners. The sunny, sheltered area on your sketch is the most valuable growing space you have, so try not to give it all to a chair.

Step 4: Decide what the balcony is for

Write one line at the top of the page that says what you want most. A place to sit with coffee? A table for two? Herbs within reach of the kitchen door? Flowers you can see from the sofa?

Most small balconies can do one main thing well and one more thing modestly. If you want examples of how others divide a tiny floor, see these small balcony garden ideas.

Step 5: Place things in order of size

Cut small paper shapes to scale for each item and slide them around the sketch. Work from large to small.

1. Seating first. A chair needs its own footprint plus room to pull it out and sit down. Place it where you will actually want to be, such as the shady end on a hot west-facing balcony.
2. Then the largest containers. Big pots and troughs are the hardest to move later. Put them in the light they need, against the wall or along the inner side of the railing, out of the path.
3. Then small pots. Fit them around the large ones in groups instead of scattering them. Groups are quicker to water and easier to walk around.

Check three things each time you move a shape: the door still opens fully, the drain is uncovered, and you can reach the railing without stepping over anything.

Think in three levels

Floor space runs out quickly, so it helps to plan by height.

• The floor is the first level and the simplest: large pots, troughs and anything tall.
• A stable stand or shelf is the second. A low, wide plant stand against the wall lifts small pots into better light and frees floor beneath. Put the largest pots on the lowest tier.
• The wall or railing is the third, and only where the building allows it. Mark these on the plan as “to confirm” until you have checked.

For ways to use height well, the guide to vertical balcony gardens goes into the options.

Leave room to grow and to water

A plan drawn with young plants in mind is too full by midsummer. Draw each container with a margin around it for the plant’s mature spread, which is usually printed on the label. Trailing and bushy plants need the most.

Think about watering too. Can you reach every pot with a watering can without moving another one? Is there a spot to set the can down? Pots you cannot reach easily tend to be the ones that get missed.

Turn the plan into a shopping list

Once the shapes sit well, trace around them and label each one. Then write the list straight from the sketch:

• each container, with its maximum footprint and the light it will stand in;
• a saucer for every pot;
• enough potting mix to fill them;
• plants, listed by the light zone they will live in and not by name.

Take the sketch and the tape measure with you when you shop. Buy the containers and plants for the floor level first, live with them for a few weeks, and add the next level once you see how the space works.