How Long Can You Store Potting Soil? Opened bags of new potting soil can retain quality for around 6 to 12 months. For unopened and unused potting soil, you can store it for about a year or two before it goes bad. Usually, potting soil lasts longer when stored in a dry and cool container.
If you have an old bag of potting soil stored on your shelves, you can count on the opened bagged soil preserving itself for about 6 months before it starts degrading. Unopened bags can last one or two years. Check your bag for specifics – it may have a best by date.
After 6-12 months most bags of potting soil have lost some, if not most of their nutritional value, but they are still safe to use. It just won't have optimal food to feed your plants. Most potting soil can be stored 1-2 years without spoiling if stored properly, but its nutrients will still degrade.
Used potting soil may contain pests and pathogens.
Insects can lay their eggs in the soil only to hatch right in time for planting season. Old potting soil can contain plant pathogens such as species of the fungus Fusarium, which is easily spread by wind or fungus gnats in moldy potting soil.
– Shelf Life of Miracle Gro Potting Mix
The miracle grow potting soil variant comes with a shelf life of about five years, it is important to know that it contains sphagnum moss, ammonium nitrate, perlite, and compost and can go bad if compromised. Therefore, store them right and use them as per its instructions.
Fortunately, most potting soil can last up to two years because that is the lifespan of the peat moss it likely contains. (Tip: To keep it as fresh as possible, store it sealed in its original bag or another covered container in a climate-controlled environment.)
One of the first signs that your potting soil has gone bad is if it starts to smell. If you notice a rotten egg smell coming from your potting soil, it's a sign that it's gone bad. The bad smell is caused by bacteria and fungi that are breaking down the organic matter in the soil.
Last year's potting soil may look ready to re-use, but odds are much of the nutritional value leached away on its first go around. Replenish lost nutrients by adding slow-release fertilizers, vermiculite or compost.
Potting soil vs. potting mix: Though these terms are used interchangeably, there is a difference. Potting soil may or may not contain soil, while potting mix is strictly a soilless medium. Potting mix is sterile, which makes it safer for plants because it doesn't contain pathogens such as fungus or other diseases.
Compost recharges and adds incredible structure the soil. The finer the compost is, the better for potting soil. Next, add in the worms castings. As for how much to add, 2 to 3 cups of castings for every 5 gallon bucket of old potting soil is a good rule of thumb.
Potting soil storage is best in an airtight zip lock bag. Place the soil directly into this bag, or you can also choose to have the zip lock bag placed over the original packaging. Keeping the potting soil in an airtight bag will make it last longer.
However, all is not lost just because your potting soil has celebrated its second anniversary. “If your potting soil has passed the two-year mark, you can still make use out of it by amending it or adding it to raised beds for support or sprinkling it on flower beds,” says Sears.
If you keep your sealed potting soil bag in a dark, humid environment, it's likely to attract mold. It's a good idea to keep sealed potting bags in places where they receive some hours of direct sunlight to keep in dry inside out.
Storing Bagged and Bulk Garden Soil
If you have a surplus of bagged garden soil, place the bags in plastic storage containers and store the landscape material in a garden shed, garage or other dark, dry area.
If it's been awhile, and your plants aren't performing well, maybe it's time you looked into it. Typically, changing the soil in your potted plants should happen every 12 to 18 months. There are some exceptions that may change this timing.
Potting soil doesn't need to be replaced every year. But the soil does need to be amended to ensure the dirt drains well and there are enough nutrients in the soil. Keep reading to learn how to reuse potting soil each year. Old potting soil can often become compacted and shrink away from the sides of the container.
If plants died from bacterial, fungal or viral disease, then you definitely do not want to reuse the soil, as soilborne pathogens can still be present and active. However, if the plants that grew in the soil before were healthy, it is generally OK to reuse the potting soil.
But you can leave plastic pots filled with soil outside all winter. Winter rains and snow may fill the pot, and freezing temperatures cause the water to expand. But in most cases, you'll see the ice cube effect with the frozen soil expanding out the top of the pot.
Legionella longbeachae, a bacteria commonly found in potting mix, can cause Legionnaires' disease, a form of pneumonia. This disease is often caused by inhaling or by spreading the bacteria from hand to mouth after handling potting mix, soil or compost.
Most often, the white stuff in potting soil is perlite – a manufactured granular product made by heating up little bits of naturally occurring glass until they pop like popcorn. That's why these little white lumps are also known as “volcanic popcorn”!
The substance commonly lurks on the surface of the soil, but may also grow below it. "Mold can present itself in various colors and may appear fuzzy, slimy, or powdery," says Josh Brown, owner of Predatory Plants. If your plants are not thriving or are showing signs of stress, it could be a sign of mold soil.
However, a little planning and inventiveness go a long way to finding suitable storage for the compost! Large ziplock bags, airtight food storage containers, stainless steel, and plastic dustbins of various sizes all make great storage options for potting soil.