Sterilising Soil

[niemeyjt]

Having tried to economise by filling planting troughs with soil instead of compost, and now having to pull a multitude of weed seedlings out every day, I am thinking how to prevent the same thing happening next year.

One option is soil sterilisation - or I think pasteurisation is maybe the correct term - to kill seeds and pathogens without incinerating the soil itself.

Commercial electric sterilsers are available - but seem small and expensive to buy and run - has anyone used them?

More interestingly - has anyone built their own - using wood to make steam maybe?

Any and all thoughts invited, thanks, Julian.

 

[jinman]

Many years ago I heard someone discussing soil sterilization on a gardening show. For small amounts for indoor flower pots, they suggested putting trays of soil into the kitchen oven at 350ｺ F / 177ｺ C for an hour to allow good heat penetration. It seems to me that compost or soil with a lot of organics might smoke a bit, but having never done it, I just don't know. It does seem possible to build a fire around a metal barrel full of soil outside. If that barrel could be tumbled while heating with wood, gas, or propane heat, the materials inside would heat evenly. If you want amounts approaching a half-yard or more, then this method might be a bit tedious.

 

[Chuck52]

In many parts of the US, we can cover a planting bed with black plastic and the temps on a hot summer day will kill or cause to sprout many of the weed seeds. It is often necessary to do that and then till the bed and do it again to expose more of the seeds to the high temperature. May not work so well in the UK.

Chuck

 

[charlz]

Soil Sterilization Instructions

Gives you an idea of the temperatures and times as recommended by the government.

 

[charlz]

In many parts of the US, we can cover a planting bed with black plastic and the temps on a hot summer day will kill or cause to sprout many of the weed seeds. It is often necessary to do that and then till the bed and do it again to expose more of the seeds to the high temperature. May not work so well in the UK.

Chuck

Clear plastic for soil solarization. Has to be tight and well sealed.

 

[Willl]

Wayne Schmidt's Soil Solarization Page

 

[Jstpssng]

Having tried to economise by filling planting troughs with soil instead of compost, and now having to pull a multitude of weed seedlings out every day, I am thinking how to prevent the same thing happening next year.

One option is soil sterilisation - or I think pasteurisation is maybe the correct term - to kill seeds and pathogens without incinerating the soil itself.

Commercial electric sterilsers are available - but seem small and expensive to buy and run - has anyone used them?

More interestingly - has anyone built their own - using wood to make steam maybe?

Any and all thoughts invited, thanks, Julian.

before the days of non-soil potting mixes, my father sterilized (sp?) the soil for the greenhouse using heat from the boiler, into a sercies of pipe about 2 feet apart in the body of his dumptruck.

Now retired, he still has an electric steriliser (sp?) as you suggested, which does about 1/3td at a time.

I don't know what you have for laws over there, but we have preemergent weed suppressants, including an organic solution made from corn gluten, called "Preen"(www.preen.com) It's a little pricey in the short run, but given the time/money I putinto my garden, it's worth it.

Who was it that said "Nothing is sure except death, taxes... and garden weeds"?