"David Hare-Scott" wrote:
anthony123hopki wrote:
Hi

I have 3 raised beds. They need topping up after settling with about
3/4 of a ton of material. I'm not sure whether to just chuck in pure
compost, or topsoil, or a mix. Does sterilised/sieved topsoil from
garden centres have any nutrients in at all? Clearly compost has
plenty but it doesn't last that long.

Any help much appreciated.

It depends on the quality of what you have and what you want to grow in
the beds. The nutrient content of commercial topsoil is very variable,
it can be anything from quite ordinary to excellent. Perhaps there is
somebody local (garden club?) who can show you how to assess such things?

How do you know you need 3/4 of a ton? Bulk materials like this are
usually sold by volume and the weight will vary according to content and
moisture. Consider if it will be cheaper in the long run to buy a truck
load and have some left over for other purposes than buy bags.

David

Assuming your talking about a pickup truck worth and dirt weighs that
amount and topping up actually means filling up the raised bed completely.

Hmmm... 3/4 ton or 1500 pickup truck bed carries which would be about
6'x3'x2'= 36 cubic feet. 36 / 3 beds = 12 cubic feet per raised bed. So
that would fill a bed that is 4' x 6' x .5' = 12 cubic feet for each of the
three beds.

So a loaded pickup SHOULD fill 3 beds that measure 4' x 6' x (1/2)' raised
beds.

I would go for a fifty fifty mix. Topsoil is good for structure, compost
for microbes and some nutrients. Could add some peat moss to lighten the
mix if the Mix seems to heavy for the plants. Carrots love a light soil and
I find tomatoes like it a tad bit heavier ( the can topple over and uproot
if soil is too light ).

If going to landscape supplier or free local compost recycler, a typical
small front loader is 27 cubic feet 3x3x3. If you go before a rainy day
that soil will be much much heavier and harder on your truck. However, I
usually get half loads with my Dakota, rated for 750 not 1500, full loads
damaged the protective bumpers for the drive shaft that cost me fifty bucks
to repair. So half loads for me.

Is that what your looking for?

--
Enjoy Life... Nad R (Garden in zone 5a Michigan)