DIY Self Watering Veggie Box

Constructing the DIY Self Watering Vegetable Box

Here are four self watering veggie boxes thriving on the patio

I hear too many folk say that they do not have enough room, enough time or enough skill to grow vegetables.  I hope this small post on how to make a self watering vegetable box will blow all that out of the water and shift a paradigm.

Planting vegetables in the ground can be a real pain to upkeep. I leave for work before the sun has risen and do not get home until well after sun-down.  The only time I can garden is the weekends or on a day off.  I do not have any time to water, tend, fertilise or upkeep my vegetables and I most certainly have no time to weed.  The perfect answer to this is to make our own self watering veggie boxes.

These self watering vegetable boxes  cost me very little as my local Coles and Woolworths are very happy to give me Styrofoam broccoli boxes from the fruit-n-veg department with lids for free whenever I ask for them.  It is important that they are not damaged or have even a single small remember to inspect them.

Using self watering vegetable boxes means I only have to water them once a week, I never have to weed, I can move them to sunnier positions if I need to, I use less than half the water I would in a traditional in-the-ground veggie plot, I can expand my garden slowly a box a time, my garden is totally contained and manageable, I can fertilise directly through the water reservoir filler tube, I never water from the top thus reducing above ground moisture and reducing pests and mold that relies on moisture, I could use these boxes on an apartment balcony or a sunny inside room too. Those of us renting their homes will find this method fantastic as we do not have dig up the landlord's yard to have a veggie garden and they are super cheap to make...maybe even free depending what we have sitting around in our shed or under the house.  Even if we had to buy everything, these boxes will last for many years.

Here is what I do to make a self watering vegetable box - I am super challenged when it comes to being 'handy' and DIYish, so if I can do this then anyone can!


1. Half fill the box with water to check for leaks - the bottom half of the box must be 100% water tight so it can be a perfect reservoir of water for your plants. Empty the water into a watering can for later use.

2. Cut the Styrofoam lid to fit exactly and firmly inside the box

3. Use three old plastic flower pots (they must be exactly the same height) as your wicks. I usually put four small holes along the base of the pots to ensure good water flow.

4. Cut three equally spaced holes in the Styrofoam lid  - make sure they are a little smaller than the tops of the plastic pots so the Styrofoam lid can sit on top of the plastic pots and take the weight of your soil.

5. Cut a tube to act as our filler pipe and position this in one of the corners of the box.  Always cut the bottom of this tube at an angle so it allows easy water flow into the reservoir. We will also need to cut a neat hole in the very corner of our lid to accommodate this too.

6. Line the plastic flower pots up across the bottom of the box and then insert the Styrofoam lid.  Push down firmly onto the pots then adjust the pots to line up neatly underneath the three holes we have cut in the lid - we do not want soil escaping into the water reservoir, so pay attention to a neat alignment here. Now insert the filler pipe.

7. Fill the three pots (now acting as our wicks) with potting mix and pressing potting mix firmly into the pots.  Then fill the remainder of our box with potting mix.

8. Cut an overflow hole in the side of the box half way up to ensure the reservoir never floods.

9. Transplant your seedlings

10. Now add a little extra potting mix to ensure the box is totally full (It will settle a little).

11. Add mulch - I use sugar cane mulch

12. Place in a sunny position - always do this BEFORE watering as we will not be able to lift the box once full of water!

13. Water using a watering can from above until the reservoir completely fills and starts to run out of the overflow hole.  This will be the only time we water from above directly into the plants and soil.

14. Water weekly by filling the reservoir using the filler pipe only.  I just pop the hose straight into the filler pipe and stop when the water starts to run out the overflow hole - a 30 second job per box every Saturday morning. Strenuous hey?!


The old plastic flower pots in position

The trimmed up lid and filler pipe ready to insert

Study this picture carefully.
Note that the flower pots line up exactly with the holes
Note also how the filler tube is a snug reaches right
to the bottom of the box.
Note also how snug the lid needs to fit inside the box to
create a strong effective barrier between soil and water.
Aim for half water and half soil.

Cutting an overflow hole at the top of the reservoir is vital otherwise
we will flood our plants and they will die.
The bottom half of the box is water (mine hold approx 16 litres)
and the flower pots full of soil act as wicks

Filling the pots with potting mix.  These will become the wicks
that draw the water up from the reservoir.

Fill the rest of the box with potting mix.
We are ready to transplant now.

Laying out our seedling to get the spacing correct.

Seedlings in.
Red Emperor Beans this time.

Fill up the box with a little extra
potting mix then pop mulch on top.
Now we move our box to its final position
BEFORE watering

The first time we water, we do it gently and evenly from on top.
This saturates the potting mix and goes down into the wicks and
drains into the reservoir.  This took two full watering cans to
fill the reservoir.
This will be the only time we water this way. All future watering
will only require us to put the hose down the filler tube
and fill the reservoir.  The pants will suck up the water
from the reservoir beautifully.

We know the reservoir is full when the overflow hole starts
to leak water.

All done and dusted and put next to my other self watering
vegetable boxes on the patio

This picture was taken at 6 am this morning with the sun just
beginning to hit the plants.
It took me 2 minutes in total to water these four boxes
using the hose directly into the filler tubes.
I only have to do this once a week. Big effort hey!?

This is easier than falling off a log folks - I promise.  The benefits are manifold too.

Lean in and give it a shot folks.

Take care and stay nice.



  1. I have found an Esky or three in the back yard that I am going to make into wicking beds once my hubby drills the holes. I have been waiting for that to happen since summer so I might need to learn how to use the drill myself :-)

    1. You'd handle a drill like a pro Nanna Chel. If old bumble-fingers here can use a drill, you surely can. Although if you use the gravel/scouria method of wicking box you can do that all and then mark where you need the bleed hole and 'himself' can drill that right at the end.

  2. This is fan..tastic Mr HM!! I've used styrofoam boxes in the past but just as planters. These are best home made wicking beds I have ever seen. Usually instructions are really complicated and my eyes glaze over with it all. I have a couple of shop-bought wicking beds but will give this a go this very weekend. It will soothe my post-voting frazzled nerves...

    1. Vote for Hutchy and save the world with her new self watering veggie boxes! That'll be my vote :-) ...Anyway, I'm glad the instruction made sense.

  3. Great post. Such a smart solution from so many aspects for growing veggies.

    1. A new box every week is the goal here at our place....we'll see if we can do it.

  4. These are a fantastic idea Phil!

    I showed these to my elderly parents a couple of years ago when I saw them on SpurTopia blog. They were having trouble with tree roots taking over their veggie garden, so I thought this was an ideal solution for them. They have had great success, especially when growing tomatoes, often getting two crops from the vines :)

    I still haven't tried them but want to. One day :)


    1. I have modified it a bit from the Spurtopia blog but the principle is exactly the same. We get maximum water storage in this version

  5. Hi Phil

    I have tried a few versions of wicking beds and they have been great. I didn't make the water reservoir big enough in my first few attempts so I have modified that. In my latest version i used some scrap reinforcing steel on a couple of pavers. However I like the look of yours but just wondering - how do you stop the potting mix escaping from the drainage holes in the pots? ps great blog

    1. We cut the styrofoam lid exactly the size of the inside of the box - it is a pretty firm fit and 'scritches' as you push it down onto the pots - I doubt little if any potting mix gets down into the reservoir.

  6. Like you I work full time and leave for work early returning home late. I have a few of these boxes lying around which I was going to plant vegies in but now I will make them self watering vegie containers. Thanks for this, just what I needed. I will post pics in forum when I have done it.

  7. thanks for your comment, I see how your wicking beds are slightly different to mine. I might try your system next time and see what the results are. I like the idea that the plants can grow deep roots right into those pots, thereby adding depth to the system. We have such a mosquito problem though that I am concerned mosquitoes could breed through the overflow, but could maybe put some mosquito netting over that.

    1. ...or just stuff an old rag down the filler tube - it does not have to be fancy to deter mozzies.

    2. ...or just stuff an old rag down the filler tube - it does not have to be fancy to deter mozzies.

  8. Great instructions. I'll be scrounging broccoli boxes ASAP!

  9. Great idea! Great instructions! Off to woollies now 😊


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