Aquaponics: Root-bound Tomatoes


We’ve had a terrific season of growing tomatoes for the last eight or nine months and right through into the Queensland winter. The one vine we had just kept producing massive amount of tomatoes month after month.
I must admit being a bit cautious about what the flavour of an aquaponically grown tomato would be like.
Would it tasty watery and lacking in flavour? We can assure you if you choose a good old fashioned variety the tomatoes you grow will outclass anything you can buy in the shops. Hands down the flavour of aquaponically grown tomatoes are exquisite.

If you plant a boring tasteless hybrid plant – and we once did – you will get a tasteless hybrid tomato. Aquaponics can grow tomatoes very well but it can’t work miracles, so choose your tomato variety carefully before planting for good results.

A good tip is to not over-plant your grow beds with tomatoes.

You only need one or two tomato plants per system to feed your family. Sometimes less is more.

But there is a trade-off with tomatoes grown in aquaponics and that is you will get rampant growth. Massive vines baring large full flavoured fruit comes at a cost.

Massive root-balls!

The tell tale signs that things are powering along below the pebbles is that the water bringing in all that lovely fish nutrient will start to pool on top of the gravel or clay pebbles.

The water doesn’t seem to sink or disappear but spreads out. Water pooling like this can indicate you have either far too much water running into your grow-beds or if there’s a tomato planted nearby. You have a root-ball problem.

Its not really a problem that worries us greatly if we are getting good growth and plenty of fruit. But after a while you need to do some maintenance because the root-ball will crowd out other plants growing nearby and you’ll notice your tomato vine is just getting rampant and out of control.

Massive tomato rootball spreads out causing water to pool in the growbed.

So reluctantly we decided to rip the plant out.

It had still plenty of green and ripe tomatoes coming along but the system badly needed some attention.

Lifting the plant out of the grow bed revealed that the root-ball does not grow down to the bottom of the trough but spreads out laterally like a thick carpet of mulch.

Any compost worms you’ve thrown into the system will adhere in this layer feeding off bacteria.

Below the root-ball the water will be a muddy brown colour and free of obstruction.

The roots will smother the pebbles and freeing them can be difficult.

A good technique is to use a plastic laundry basket to wash and drain the roots, free the pebbles and allowing them to be reintroduced back into the system.

Some people just let them dry out in the sun for a few days, loosening the roots, making them more brittle and easier to dislodge.

This same plastic laundry basket was also used as a nursery tank for our small baby Jade perch. Because larger fish will eat baby fry, you’ll need to separate them so an inexpensive basket like this was placed in the fish tank until the fish got larger and able to fend for themselves.

Murray Hallam’s Aquaponics Secrets also covers laundry baskets and other innovative uses including salt baths plus heaps of Aquaponics related information. Get the triple set DVD pack from Murray’s website if you’re interested in learning more about this subject.