Balcony & Windowsill Pot Planner

A small growing space can hold more pots than you might expect — but only if the pots actually fit.

The Balcony & Windowsill Pot Planner helps you estimate how many containers can fit inside the space you have.

Enter the usable length and width of your balcony, windowsill, shelf, patio corner, or other small growing area. Then add the size of the pots you want to use, the gap you want between them, and any space you want to keep clear.

The planner will show you a simple layout and estimate how many pots can fit.

It is useful before buying containers, rearranging a small garden, or trying to decide whether a new group of herbs or vegetables will fit in your space.

Start with the space you can really use

A balcony may be 2 metres wide, but that does not always mean you have 2 metres available for pots.

You may need to leave room for:

• a door to open;
• a chair or small table;
• a walking path;
• a drain;
• an air-conditioning unit;
• a railing gap;
• access for watering;
• another planter already in place.

The same idea applies to windowsills.

The full width of a window may be large, but the flat area where pots can safely stand may be much smaller.

Measure the part you can actually use.

Measure length and width

For a balcony, shelf, or rectangular growing area, measure the usable length and width.

Try to measure in a straight line.

Do not include corners that are blocked by furniture or parts of the area where a pot cannot stand properly.

For a narrow windowsill, width becomes especially important.

A pot may fit from left to right but still be too deep for the sill.

If the pot hangs too far over the edge, that is not a good fit just because the planner can place it inside a simple rectangle.

The planner helps with space planning. You still need to check that the real surface is suitable for the container.

Use the pot’s widest footprint

When you enter pot size, use the width of the part that takes up the most floor or shelf space.

For most round pots, this is the widest outside diameter.

This is different from the soil calculator, where inside measurements are more useful.

Here we are planning physical space, so the outside size matters.

If the pot has handles, a wide saucer, feet, or a decorative outer cover, include those too.

A 20 cm nursery pot sitting inside a 26 cm decorative planter really takes up about 26 cm of space.

Do not pack the pots too tightly

If several pots technically fit side by side, that does not always mean they should touch.

A little space between containers can make the garden easier to use.

Gaps can help you:

• reach the pots for watering;
• remove one container without moving everything;
• clean fallen leaves;
• check plants for pests;
• allow leaves to spread;
• avoid trapping every pot against the next one.

The planner lets you add a gap between containers.

This gap is not a gardening rule.

It is simply the amount of breathing room you want in your layout.

For small herb pots, you may be comfortable with a small gap.

For large vegetable containers, you may want more room.

Pot spacing and plant spacing are not the same thing

This is important.

The planner works with the pot footprint.

It does not know how wide the mature plant will become above the pot.

A 25 cm container may hold a plant that eventually spreads 50 cm or more.

This is especially important for plants with large leaves, trailing growth, or branches that spread sideways.

So a layout that fits six pots on the floor may feel crowded once all six plants are mature.

The planner answers:

How many pots can fit here?

It does not always answer:

How many mature plants should I grow here?

Leave room to reach the plants

The maximum number of pots is not always the best number of pots.

Imagine you can fit 12 containers on a balcony, but the back row becomes impossible to reach without lifting the front six pots every time you water.

That layout fits on paper.

It may not work well in real life.

This is why the planner includes space for access or reserved area.

Use it.

Think about how you will:

• water the back pots;
• turn containers;
• prune plants;
• harvest herbs or vegetables;
• clean the floor;
• move a sick plant away from the others;
• open nearby doors.

A slightly smaller garden that is easy to care for is often more useful than the maximum possible number of pots.

A simple balcony example

Imagine you have a small growing area that is 180 cm long and 90 cm deep.

You want to use round pots that are about 30 cm wide.

You could enter:

• 180 cm available length;
• 90 cm available width;
• 30 cm pot diameter;
• the gap you want between pots;
• any space you want to keep clear.

The planner will estimate how many rows and columns fit into that area.

You can then look at the layout and ask a second question:

Would I actually be able to water and care for all of these pots?

If the answer is no, increase the gap or reserve more space.

The largest number is not always the best result.

Why changing the pot size can completely change the layout

Small changes in pot diameter can make a big difference in a small garden.

A balcony may fit three 25 cm pots across one row but only two 30 cm pots.

That does not sound like a big difference in pot size.

But across several rows, it could change the total number of containers quite a lot.

More pots are not always better

When you see unused floor space, it is tempting to fill all of it.

But plants need more than a place to stand.

You also need to think about:

• sunlight;
• watering;
• airflow;
• mature plant size;
• support stakes or trellises;
• drainage;
• access.

A crowded balcony can also become harder to clean and manage.

The planner is best used as a starting layout.

Once you know what physically fits, decide whether that number also makes sense for the plants you want to grow.

Think about where the water will go

Container gardens need drainage.

That means water has to go somewhere after it leaves the pot.

On a balcony or windowsill, this matters more than it does in an open garden.

Check whether you need:

• saucers;
• trays;
• pot feet;
• a protected surface;
• a clear path to a drain.

Remember that a saucer can be wider than the pot itself.

If you plan to use saucers, measure their width and use that as the container footprint if it is larger than the pot.

A layout that only measures the pot may be too tight once the saucers are added.

Windowsills need a little extra care

A windowsill is usually much narrower than a balcony.

Before placing a pot there, check three measurements:

• the usable length;
• the usable depth;
• the outside size of the pot.

The full base of the container should have a suitable place to stand.

Do not assume a pot is a good fit simply because most of it fits on the sill.

Also think about curtains, blinds, windows that need to open, and water that may drip onto the wall or floor.

What about pots on a railing?

A railing planter is different from a pot sitting on the floor.

This planner can help you think about horizontal space, but it cannot tell you whether a container is safely attached to a railing.

The correct support depends on the railing, the planter, the mounting system, the wind, and the final weight of the wet container.

Treat railing safety as a separate question from layout.

Do not use the number of pots shown by this planner as proof that a railing can support them.

Wind can change a good layout

A sunny balcony can also be a windy balcony.

Tall plants and large leaves can catch the wind.

Lightweight pots can move or tip more easily than heavy ones.

A layout that looks good on a screen may need to change if one side of the balcony is very exposed.

You might choose to keep taller plants closer to a protected wall and shorter containers in more exposed positions.

The planner does not measure wind exposure.

Use what you know about your space when you arrange the final pots.

Sunlight may not be equal across the whole balcony

One side of a balcony can receive several hours of direct sun while another side stays shaded by a wall.

The planner treats the growing area as one rectangle.

Sunlight does not always behave that neatly.

Before you fill every available spot, watch how the light moves across the space.

A pot may fit perfectly in a corner but still be a poor place for a sun-loving vegetable.

Physical space is only the first part of the plan.

Leave room for doors and walking

Before you buy the pots

A few quick checks can prevent a layout problem later.

What this planner can and cannot tell you

A layout tool is useful, but it cannot see your real balcony or windowsill.

Frequently asked questions

How accurate is the Balcony & Windowsill Pot Planner?

It gives a simple space estimate from the measurements you enter.

It works best when the growing area is close to a rectangle and the pots have a clear outside size.

Real spaces can include corners, doors, pipes, drains, furniture, and other obstacles that the planner cannot see.

Use the result as a starting layout.

Should I measure the inside or outside of the pot?

For this planner, use the outside measurement.

We are trying to find out how much physical space the container takes up.

If a saucer, tray, or handle is wider than the pot, measure that instead.

How much space should I leave between pots?

There is no single correct gap.

Leave enough space to water, move, and care for the containers comfortably.

Remember that mature leaves may spread beyond the pot.

Why does the planner show more pots than I think I should grow?

Because it calculates physical pot space.

It does not know how large the plants will become.

A group of small pots may fit neatly while the mature plants above them become crowded.

Can I use the planner for a windowsill?

Yes.

Measure the flat usable length and depth.

Make sure the pot base is suitable for the real surface. The planner cannot decide whether a narrow sill is safe for a particular container.

Can I use this for shelves?

Yes, if you treat each shelf as a separate rectangular growing area.

You should still check the shelf’s real weight limit yourself.

Can I use this for railing planters?

You can use it to think about horizontal space.

It does not check the strength of the railing, mounting hardware, planter, or supports.

Does the planner calculate balcony weight?

No.

It does not calculate structural load capacity.

Wet potting mix, containers, plants, water, furniture, and people can all add weight.

If weight is a concern, check the building information or get suitable professional advice.

Does it know how much sunlight each pot gets?

No.

The planner only uses physical dimensions.

Watch your space through the day to see where direct sunlight actually reaches.

Can I mix different pot sizes?

The simplest result comes from planning one pot size at a time.

If you want several sizes, run the planner more than once and use the results to build your own mixed layout.

Should I fill every available space with pots?

Not necessarily.

Leave enough room to reach your plants and keep the area comfortable to use.

More pots are only useful if you can care for them.

Plan the plants after you plan the pots

Once you know how many containers can fit, the next question is what to grow in them.

You can continue with:

Vegetable & Herb Pot Size Finder
Check whether the pot size you are considering gives a crop enough root space.

Small-Space Edible Plant Finder
Find herbs and vegetables that better match your available sunlight and container size.

Container Soil & Grow Bag Calculator
Work out how much potting mix your final group of containers will need.

Container Garden Budget Calculator
Estimate what the complete setup may cost before you shop.

Are my measurements saved?

You do not need an account to use this planner.

The measurements you enter are calculated in your browser by the tool.

You can also use your browser’s print option to print the plan or save it as a PDF.

One last thing

A good small-space garden is not the one with the most pots.

It is the one you can reach, water, enjoy, and keep growing well.

Use the planner to see what fits.

Then leave enough room for the plants — and for yourself.