How To Grow A Crepe Myrtle From Cuttings Or Seed

Plant propagation is a great way to grow new plants from old favorites. With a few extra planters, good potting soil, water, and a little patience, this is a cost-effective way of multiplying plants for your own landscape or to share with others.

Before getting started, it's important to know that it is an infringement of copyright law to use asexual propagation or to grow from seed a trademarked or patented cultivar. Plant patents last for 20 years and will be noted on the plant tag with a “PP” and a series of numbers or “PPAF.”

The good news is that many crepe myrtle varieties have been around for a lot longer than 20 years, and those older varieties are safe to propagate. Gardeners can use this method to bring along a living memory of a favorite family tree when moving to a new home, to help in land restoration projects, or to welcome a new neighbor with a plant that is a part of your own home. Propagation for crepe myrtles is best done through the summer months and can easily be done through several methods. Here's how:

Propagating Crepe Myrtle from Cuttings

One of the easiest and most common ways to propagate a crepe myrtle is from semi-hardwood cuttings taken during the growing season. 

What You’ll Need: 

1. A clean and sharp hand pruner
2. A 5-8 inch wide planter with holes in the bottom for drainage. If reusing a nursery pot, wash thoroughly with soap and hot water. 
3. A growing medium: clean sand, a mixture of one part sand and one part peat, or a potting mix 
4. A rooting hormone (not required, but helpful)

Where to Cut:

1. Take a 6-8” cutting of new growth. It is best to make your cutting where it joins the branch and ensure that it has least 3-4 leaf nodes. 
2. Remove all the leaves but keep several leaves at the tip of the cutting. 
3. Fill a small planter with growing medium and water well before inserting the cutting. 
4. If you have rooting hormone, dip the cut end into the rooting compound up to about 3 inches. Carefully stick the cutting into the planter about 4 inches deep.
5. Gently water the newly planted stem but do not soak it. 

Maintaining the Cutting: 

1. Place newly planted cutting in indirect bright light. 
2. Keep soil evenly moist for the next 4 to 6 weeks. 
3. Tips: Propagating more than one cutting at a time is a good idea. Opaque large storage boxes can be turned upside down and placed over the planted cuttings to act as a greenhouse effect to hold in moisture. 

When to Plant the Cutting

After 6 weeks gently pull on the cutting to see if rooting has occurred. If you feel resistance there should be roots. Plant in the fall in full sun and keep regularly watered throughout the first year. 

Cuttings can also be planted directly into a prepared outdoor rooting bed. Dig a hole or small trench about ten inches deep and mix soil with about five inches of peat moss, sand, or pine fines to fill hole. Follow all the directions above except insert cuttings into the bed and keep bed moist until the fall when rooting plants will be ready for transplanting. 

Growing Crepe Myrtle from Seed

Growing crepe myrtles from seeds is also an easy way to multiply your crepe myrtles, but it is a bit slower to produce a tree that is ready to be planted in your garden. 

What You'll Need:

1. Glass jar or airtight container for holding seeds
2. 4-6 inch pots 
3. Seed starting mix

Collecting Seed Pods in Autumn: 

1. After flowering, the crepe myrtles produce seed pods. After they have dried into a dark brown pod, squeeze them over a shallow bowl and shake the seeds out. 
2. Place seeds in an airtight container and place in a cool, dry location until the following spring. 

Planting Seeds in Late Spring: 

1. Fill your 4” or 6” pots with seed starting mix and saturate the soil. 
2. Push 2 seeds into the soil about ¼” deep. 
3. Mist soil with water. 
4. Cover pot with a small ziplock bag and only mist with water when soil appears to dry out. 
5. Place pots indoors in a warm sunny spot. 
6. Option: Use a seed starting heat mat during the germination period.
7. Germination takes about 3-4 weeks. Then you'll start to see sprouts appear. 
8. When sprouts are 2 inches tall remove the zip lock bag and continue regularly misting plants to keep them moist but not saturated. 
9. When the plant is about a foot tall you can move the plant outdoors to a partial sun location that is protected from afternoon sun. Continue to keep soil evenly moist throughout the summer into early fall when your crepe myrtle seedlings will be ready to be planted in their permanent location.