Preparing raised beds

[walksen]

I've recently built 2 concrete raised beds on a sloped part of my garden. They are about 7 0 cm square internally and about 25 cm deep at one end and 45 at the other ( due to the slope).

At the moment I've not planted anything as I read the concrete could leech lime etc. At this time of year I figure it may not be worth planting anything.

Do my question is should I leave them empty until spring then fill with soil and compost or is there something else I should be doing?

Not sure what I'll plant yet.Thinking fruit like strawberries and raspberries or maybe a vegetable or two. Not an experienced gardener by any means!

I would fill them with top soil and soil conditioner (decent bought compost, homemade compost, horse manure, leaf mould for eg) and then cover with cardboard and/or weed membrane to prevent them getting filled up with weeds over the winter. That will get the soil organisms and worms into the soil prepping it for you ready for whatever planting you do. I have done this with my own raised beds before and have had very successful growing season following this treatment.

Thank you!

Also, the soil will settle over winter, and you'll be able to see whether to top it up in spring.