How do self-watering GrowBoxes work?

This picture shows a cut-away view of a GrowBox. The reservoir in the base is filled with water through a tube from the top. Our specially designed potting mix then draws this water up at the perfect rate for your plants. A simple indicator lets you know when the reservoir needs topping up. No more guessing if you are over- or under-watering your plants!

Self-watering GrowBox planter

What potting mix do you recommend?

In our tests we have found that Daltons Premium Potting Mix performs well in the GrowBoxes and is available from most garden centers and hardware stores.  Alternatively any premium potting mix with coconut coir (also known as coconut fibre) and pumice should work.  If you have any questions please don't hesitate to contact us.

What plants will grow in self-watering planter boxes?

Most plants will perform well in our self-watering GrowBoxes. In particular, lettuce, tomatoes, cucumbers and soft-stemmed herbs such as basil and parsley absolutely love the GrowBoxes. However, some plants prefer drier conditions and therefore may not perform as well in a GrowBox.  Dry-loving plants include rosemary, thyme, oregano, tarragon, marjoram and caraway.

How long does the potting mix last?

Our standard self-watering potting mix contains controlled release fertiliser designed to last for 12 months. Because of this, if you are not changing the plants in your GrowBox, you will need to add fertiliser after about 12 months or your plants will run out of “food”. In this situation, the potting mix should last at least 2-3 years before the structure of the potting mix breaks down.

If, however, you change the plants in your GrowBox (e.g. you are growing annual flowers or a crop such as lettuce or tomatoes) the situation is different. When you remove the plants, some roots are left behind and these can rot and introduce fungi that are harmful to the plants. Lettuce has a relatively small root system and the roots left behind aren't enough to cause any issues within the 12-month life of the fertiliser. Plants with a large root system, such as tomatoes and cucumbers, however, require the potting mix to be replaced after each crop as the number of roots left behind could potentially create problems.

What happens if it rains?

There is a bung at the top of the reservoir which is removed during setup. Any excess water will just drain out through this. Our special potting mix has been designed to hold the correct amount of water for your plants. This means that even if it rains the mix will not become waterlogged.

What areas do you service?

GrowUrban Limited currently services from Whangarei to Rotorua – refer to the shipping map below. If you live outside our service area, or are unsure whether you are in our service area, please contact us.

GrowUrban Service area