Q.How To Fill A Raised Bed.
I have brought a raised bed 120x90x30cm. I intend to grow strawberries and want to know the best way of filling it. My thoughts are to shred dead plants including lilac and lavender as a base. I would add home made compost, manure and garden soil as well as shop brought top soil. Do you think that would be ok? Also do you have any other ideas, particularly inexpensive ones?

Certified GKH Gardening Expert
Soil from a garden plot will be too thick, especially with adding compost. The article included goes over it in more detail. You want as loose of a soil as you can get. If you go with garden soil instead of compost, make sure you loosen it up with extra perlite or vermiculite. It'll need to be mixed very thouroughly.
Now if this is premixed garden soil, and not from your garden plot, then you will want to leave out potting soil. Usually, pre-bagged mixed will have been mixed correctly.
One more thing. I looked back and saw where you had mentioned topsoil. Again, I would either leave it out, or if it is very loose, then replace half the compost with it. You really just don't want to compact the soil in a raised bed. It leads to problems later when it compacts at the bottom of the bed.

Certified GKH Gardening Expert
I think that you could get away without the garden soil, and mix what you have, except for the shredded plants. You may want to compost those separately if it is green material. Strawberries are very forgiving, and many types are considered invasive in my area. Actually, I can't control them, and they have traveled all around my house in very poor soil.
Here are some articles that will help:
https://www.gardeningknowhow.com/edible/fruits/strawberry
https://www.gardeningknowhow.com/edible/vegetables/vgen/raised-vegetable-gardens.htm

Thanks although I'm not sure what you mean about not adding garden soil. the majority of the fill will necessarily be garden soil.