Limestone is a naturally occurring mineral that can make acidic soil more alkaline. It falls on the opposite end of the pH scale. Some people add it to soil to achieve a better balance, but some gardens, especially rock gardens, naturally have limestone soil. Many flowers can't grow in this type of environment, whereas others prefer the alkaline-based soil.
Talk to the experts at a garden center or nursery about which plants do the best in your alkaline soil. Those that thrive in acidic soil should not even be considered, because they won't survive.
Select flower varieties such as silver cup, irises, roses, maiden pinks and cyclamen. These will grow well in a high-alkaline environment.
Work a pitchfork 4 to 5 inches into the soil. Till the soil to loosen it so you can easily dig holes for the plants.
Lay the flowers out in their pots to determine how you will design your garden. Shorter flowers should go in the front and taller ones in the back. If you're planting ground cover, place them between the other plants or all together for a blanket-type look.
Dig a hole for each flower with a trowel. The size will depend on the size of the plant. If you're putting in 4-inch plants, make the holes 6 inches in diameter. Dig them deep enough that the top of the plant is level with the surrounding ground.
Remove the flowers from their pots carefully, being certain not to rip the roots. Place them in their holes and fill the space with the soil you dug up. Pack it down lightly.
Water generously. Continue to water every two to three days, keeping the soil moist.