Does the base have to be made with Cinder Block (CMU)? Can I use solid Landscape Block?

No and Yes!

Cinder Block is great for building a base fast and cheap… and most people put some type of finish over the block, so it’s a great choice to build your base with. Landscape Block is an excellent way to build your base and have an awesome, natural finish on your base. Here are some pros & cons of both…
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Cinder Block -

PRO: Inexpensive and can be found everywhere! Average price is around $1.75 per block.

PRO: The cores can be filled with rebar and cement… It would take a bomb to move that base!

PRO: Little to zero masonry experience needed to keep every layer level - mortar fixes that!

CON: Gray block is NOT very sexy. You will need to cover up the ugly with masonry veneer or paint!

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Landscape Block -

PRO: No matter the color or texture… it’s a beautiful block!

PRO: No finish needed… they are already finished!

CON: No rebar… you will need to use a lot of masonry / landscape wall adhesive to keep it together.

CON: $$$$!!!