Seeding Objects In Concrete

 Seeding is the addition of small objects to wet concrete that will later be revealed during the polishing process. Depending on what is seeded into the mix, the effect can be very subtle or very dramatic.

Objects can be seeded into wet concrete two ways. One method is by hand immediately after concrete is poured and bull floating is completed. The seeding material is spread over the surface of the wet concrete and then embedded in it carefully. If not fully embedded the seeding material could pop out during polishing and leave holes in the surface of the floor. This method offers flexibility if you want to isolate the seeding in one area or create a design with the material. Another method is direct batch, where the seeding material is blended in to the mix at the concrete plant. This method can create a more consistent appearance, but also uses much more seeding material and can therefore be more expensive. 

What can you seed? Many different things can be embedded in wet concrete that is to be polished later. You will want to use objects that won’t melt, disintegrate, or in any other way be irreversibly damaged during the polishing process. Items that are a similar hardness as the concrete are usually a good choice. These are a few items that have been seeded successfully:

• Glass 
• Contrast color or mixed color aggregate
• Same color aggregate to match concrete mix or dye
• Marble Chips
• Metal objects (nuts, bolts, screws, coins, hardware of all sorts, wire, etc)
• Gem stones
• Geodes
• Shells
• Some plastics
• Combinations of materials of various sizes, shapes, and colors

The possibilities grow when you combine seeding with dyes, saw cuts, and other decorative concrete treatments.