I would start over. That way you can choose the size of your gardens and their placement. The low edge of rocks in the picture doesn't give you much of a side to your raised bed. You will need to build a complete bed so that fence isn't used as the back of the bed. Can't quite tell from the picture but could you use the low wall as one wall of your bed? Remember not to make the beds too wide, since you can't access from the fence side. And make sure that it will receive adequate light and not be shaded by the fence too much. If the fence is yours, perhaps it would make a good location for a trellis to gain some vertical growing space. Good luck!

Hmm,

Thank you for your time and suggestions. This area will get a lot of sunlight regardless of the fence.

I was thinking I would section off a 4x4 foot area within this bed by simply mounting some cheap timber into the soil to section it off.

I guess my real question relates to the soil and "raised" method.

Will there be significant difference based on whether or not I build the beds into this existing bed, versus adding the beds on top of these existing beds?

See they are currently "common land" so I can't hack it all away right now and have to build into/on top of what's there, for now at least.

Let me know please?

Thanks again!
Sean

Not sure what you mean about common land, but since you have moved in recently and don't know what is even planted there (one of the plants looks like a day lily) or what the soil is capable of, I would be inclined to say, don't disturb that particular section yet. Use just the front yard area that already has raised beds. Even then, there might be some perennial plants hidden in there but at least it is already in the form factor that you wanted for SFG without additional effort on your part.

Starting a new garden is lots of work and you might appreciate doing it in small steps over several months or even years, to get it to what you really want. A bonus of this approach is that this year's compost efforts can be used in your new beds next year, so you don't have to buy every single little thing for a quick bed creation this year. (And it may be in line with your comment about not being able to use the common land ... for now)

Now as for the soil, you still don't know either what the front yard beds are capable of, but at least you can start here with new soil. Don't totally throw away the old soil, you can use it in other ways once you determine how much space you want/need for gardening.

One of my common ways to use old soil is for compost bins or to mix with other amendments for things like annuals and flowers -- I don't necessarily care that they produce large quantities of blooms as much as I care about adding a bit of something something to the old soil I am reusing, for those kinds of plants.

The other part is that annuals respond to liquid or foliar feeding just as well growing them in great soil.