[Womble1]

Hi all.
        Recently aquired an allotment that hasnt been worked for Donkeys & has Jap Knotweed in 2 corners of the plot.Having strimmed the whole plot down to the ground I would now like to plant in raised beds made of old scafolding planks.My questions are,Do I really need to dig the ground beneath the frame of the raised beds (they are 9inch high Scafolding boards)or do I just need to fill the frames with well rotted h/manure & Top soil ?

Also is there (really) any differance between John Innes No3 & Screened Top soil ? Given that I would need a whole lotta either to fill these beds! & John Innes No3 isnt the cheapest option by far.

Any help with the above would be most welcomed.

Dave.

[Yorkie]

Hi Womble, welcome to the forums

Your reference to Japanese Knotweed concerns me - it's a notifiable plant so if it hasn't been killed off, I'd suggest contacting your local authority who should do something about it.

If the soil hasn't been broken up in ages, I would break it up by digging just in case there's a pan (hard compacted layer)

JI No.3 is a soil-based compost with a specified blend.  I'd guess it is sterilised and predictable in quality.  Topsoil is of less certain predictability and quantity, sometimes it's actually subsoil being sold by a less than reputable supplier.  Other suppliers will be fine.  If you can get a recommendation for top soil, I'd go for that, mixed with the manure (check its source isn't contaminated with aminopyralid) as you mentioned.

[Womble1]

Hi Yorkie,
              The knotweed put me off taking the plot in the first place & I did inform the Council who replied & I quote 'Yes we did used to treat it but we dont bother anymore' . So it was a take it or leave it plot & as they say beggars cant be choosers! so I took it. To be honest Im much more interested in growing fruit trees (apples/pears/plums etc) having somwhere to go & chill out & to keep a few chucks than actually growing veg but I have to show willing to keep the council sweet.Along with the plot being some 150 yards from the nearest vehicle access,having no building at all on the plot & not being the fittest Human on the planet to carry materials up to the plot & of course the Knotweed, the more I think about it I wonder if it was a good descision to take it on in the first place.Im at present covering as much of it as possible with large tarpaulins to try & keep growth down to a minimum & just trying to do a bit at a time.Thanks for your input on the soil.

Dave.

Just a thought if theres anyone in the Tyldesley Area of greater Manchester who has a plot with good vehicle access who is looking for a plot partner,I have a small pickup truck & a gift for comming across many usefull items that can come in very handy on an allotment & would be prepared to supply a decent shed/building as a thankyou of such,just give me a thought as we could Im sure come to a mutual agreement.

Dave

[Trillium]

9" deep is not much depth for anything other than lettuces, radish and young beets. You'd really need to loosen that lower level below the boards so that drainage improves and thirsty roots can move down easily. Also, if you want mostly trees then you'll need to dig down deeply and improve the soil. Those are long term plants and need proper soil conditions if you expect good harvests.

[matthew2riches]

Top Soil = FREE (from the right place)
John Innes No3 - RATHER EXPENSIVE