Lava rock is formed from liquid lava expelled from a volcano. As the lava discharges, minerals and gas bubbles are ejected with it. These minerals and gas bubbles cool with the lava and the compound solidifies. This process locks the gas bubbles into the rock. Iron oxidation occurs during the cooling stage, and red cinders meet the steam that is expelled, creating red lava rock. The minerals that are expelled with the lava also give the rock a red hue.
Lava rock is porous and pumice-like. It is lightweight. Red lava rock retains its color and vibrancy. It provides natural insulation and weed control. The rock does not move and is not damaged from foot traffic. Lava rock protects garden plants and the delicate roots of young plants. Because it occurs naturally, it is stable at low temperatures. Lava rock is soluble at a pH of 8.2.
Lava rock is used in decor, grease absorption and aquatics. You can absorb grease in your barbecue grill by placing lava rocks on the top of your grates, or use lava as a decoration by adding it to a flat dish or bowl and setting it on a table. You can also add lava rock to driveways, pavilions, pool areas and walkways for function and appeal, or insert red lava rocks or gravel into your fish tank to stabilize alkalinity and calcium levels. Sea creatures use lava rock to create their skeletons and shells. Red lava rock is also appropriate for propagating bacteria because it is porous. The most common use of red lava rock is landscaping.
In addition to creating driveways and walkways out of lava rock, you can also place it next to driveways and walkways to protect your grass or other landscaping beds. You can also add lava rock to your flower beds and bushes for visual appeal. Boulders are lightweight and can be used as a focal point in your lawn or garden. You may want to add lava rocks to the bottom of your pot before putting in the dirt and plant for added drainage, or place the rocks on the top of the dirt inside the pot to encourage moisture retention.