How to Divide Moss Phlox

You should divide moss phlox plants in either the early spring or late summer to early autumn, once every three to four years. This will ensure that your moss phlox perennials continue to flourish in your garden, and it's an inexpensive way to replace aging or dying plants without spending a pretty penny at the nursery.

Difficulty: Moderately Easy

Instructions

Things You'll Need:

• Shovel
• Spade
• Knife or other cutting tool
• Enriched soil
• Fertilizer
• Garden hose

1. Find the center of your growth of moss phlox. They grow and spread quickly over large areas, and you're going to need to locate and isolate the root system of the plant in order to divide it successfully.

2. Clear a large hole around the roots of your moss phlox plants, digging deep enough into the soil to ensure that you can lift the roots right out. Many gardeners find it helpful to dig deeper than necessary, then use the mouth of the shovel to push the entire root up out of the ground.

3. Use a garden hose to wash off any dirt or soil that's caked onto the plant's system of roots.

4. Take a cutting tool and cut into the crown or heart of the roots, which you can identify as the bulb-shaped cluster that forms the central hub of the root system. As with all perennials, you're going to want to divide the crown of the roots down into several divisions of at least a couple inches in size. You should make sure that there are at least several healthy root offshoots attached to each division.

5. Dig a hole in which to plant your divided moss phlox roots. You should aim for slightly more depth than the original roots reached, since the plants are really going to take off once the soil around them is dry and arid. Planting the newly divided crowns a little deeper helps ensure slower growth during the initial stages of the new plant's life, during which the ground must be kept much moister than moss phlox normally likes.

6. Keep the soil around your transplants very moist for the first few days. When the plants gain a foothold and blooming starts to take off, ease off on the watering and watch your moss phlox flourish in dry, firm soil.

Tips & Warnings

• After your new moss phlox plants have bloomed, you can shear them, reducing their volume by about half, to encourage more compact growth if you don't want these fast-spreading plants to stretch too far.