Monday – Friday: 7:00am – 5:00pm
Saturday: 8:00am – 4:00pm
Sunday & Public Holidays: 8:30am – 3:00pm

Does Garden Soil Go Bad?

Garden soil, does anyone else either have way too much or never enough? There seems to be no happy medium for planting time; either we’ve overdone it with the potting mix or haven’t got nearly enough. This has created a tendency to buy more potting mix than necessary.

But it got us wondering, does soil go bad? A disregarded bag of potting mix can easily gather dust in our back sheds. Could it be harming your garden by using an old potting mix?

We decided to investigate, and here’s what we found.

Yes, garden soil can go bad!

You can expect an opened package of potting mix to deteriorate in nutrients levels in 6 months.

You might be hunting the soil packet for an expiration date, and you most likely won’t find one. Even with a sealed bag of potting mix, it doesn’t have an eternal shelf life.

We recommend using a sealed bag of potting soil within two years of purchase.


It comes down to the ingredients within your garden mix. One primary ingredient of potting mix, peat moss, is actively decomposing in a sealed bag of garden soil. This organic matter along with other key elements like vermiculite, perlite and pine bark in your mix, accelerates the decomposing process.

The potting mix goes bad due to old plant material, which encourages mildew, mould, pests and fungus, which is not the way to take care of your plants!

Hence why potting mix may go bad before regular garden soil. If you find an old bag of potting mix with no tell-tale signs of freshness, it’s better safe than sorry to use on a large outdoor garden surface than for indoor potting plants.


  1. Bad smell
  2. Insects present 
  3. Discoloured or mouldy 
  4. Too compacted

As long as your bag doesn’t have any of these elements present, your potting mix can be salvaged.

With some added nutrients, that old bag of potting mix can be given a new lease on life. Try adding in hydrated coconut coir in equal amounts to the potting mix to give the soil the nutrients kick it needs.

Of course where and how you store your garden soil will also impact its freshness. With your growing garden collection it might be worth buying less bags more often to ensure the freshness of your mix. Speaking of garden soil, are you in need of some?

Check out our extensive range of garden soils on our website. Our range includes landscape mix, special lawn mix, native soil mix, veggie mix, general garden mix, soil conditioner and mushroom compost.

Don’t hesitate to reach out with any garden soil related questions!

Contact us