On Thu, 18 Mar 2021 23:50:02 -0400, Michael Trew >
wrote:

>On 3/18/2021 12:32 PM, Sheldon Martin wrote:
>> On Thu, 18 Mar 2021 US Janet wrote:
>>>
>>> I originally went to Costco to pick up 4 bags of potting soil for $9
>>> each but they were all sold out. Apparently you need to get to the
>>> store when it first opens to get the potting soil. I guess a lot of
>>> people are getting into gardening these days. Another shipment is at
>>> the warehouse in Salt Lake and should be at the store by today or
>>> tomorrow.
>>> I just phoned Costco and the potting soil is in. Off to Costco!
>>
>> It's very easy to make your own potting soil, better quality and costs
>> less. Buy a bale of peat moss and a bale of sterilized compost. Mix
>> them together as needed and in a proportion you like. Be sure to buy
>> sterilized compost as any weed seeds it contains will have been cooked
>> dead. If you decide to buy Costco's potting soil be certain it's
>> sterilized or you will have a ton of weeds.
>
>I thought that I was nuts when I had weeds growing from pots and I
>suspected it was in the potting soil. I figured a commercial product
>like bagged potting soil would be free seeds and the like... guess not.

If you had weeds in a pot that you were growing indoors, then yes, the
potting soil had not been sterilized. Outdoors however, the air is
full of seeds. The wind can blow them in from several states away.
Most probably the weeds are from something that recently bloomed
nearby.
Janet US