Airing a Problem Out? Air-Sacks

by Kev
(UK)

I suppose like many people I am feeling the penny-pinch and so I look at cheaper ways of achieving similar results that 'high-end', expensive gardening products are supposed to give.

One such item I saw today is an 'air-sack'. Essentially it's a breathable membrane into which you put your compost/soil mix. This works by allowing roots a greater surface area to access oxygen.

That costs.. wait for it.. a whopping GB£15 each! I can buy a breathable recycling bag of the same size for £0.45p! My question is very simple: how would this affect both a root crop and a fruiting crop, please, as opposed to traditional solid plastic plant buckets?

Answer: Kev- To tell the truth, I imagine these bags will affect plant growth very little. As long as your bags have holes to drain out the bottom, and as long as you are using a lightweight (easily drained) grow medium, you should have no problem with a lack of oxygen at the root level.

Mathematically, the only way to increase the surface area of the roots is to grow more roots! It is true that nutrient absorption only takes place in the presence of oxygen, but the bags you refer to will neither increase the oxygen at root level nor will they stimulate your plants to grow extra roots.

This is one product I would not bother purchasing....it is always better to reach for great results using affordable products than to purchase ANY product without knowing 100% how it is supposed to benefit your plants. Every product out there claims it will increase the growth or yield of your plants by 20% (or some other number)....the problem is, if you know what you are doing and are already getting good results, the chances of you seeing that extra 20% from ANY product you purchase is unlikely. This is true even for the really good products like vitamin B1 or liquid seaweed.

Luckily, as you get more gardening experience, you are able to tell more easily which products are really needed to produce results and which are not. In this case, your gut is correct....this is a product you do not need!