If you’re looking to add a splash of color and elegance to your garden, bearded irises are a fantastic choice. Known for their striking blooms and hardy nature, irises can thrive in San Antonio, Texas, with the right care and attention. In this blog, we’ll explore the best practices for planting and caring for bearded irises in this region.

Planting Bearded Irises: Rhizomes and Transplants

To plant a bearded iris rhizome, dig a hole about twice the size of the bulb, place the bulb with the pointed end up, and fan out or spread out any roots on the rhizome when placing it in the soil. Then backfill the hole, covering the iris rhizome with soil, leaving the top just about an inch below the surface.

For transplants, dig a holes deep enough to accommodate the root systems of irises, and about twice as wide as the nursery pots. Set the transplants to where the soil level in the nursery pot is level with the top of the planting hole. Back fill hole and gently but firmly press down soil around irises to ensure good soil contact with roots.

Planting irises 12-24″ apart is a good rule of thumb for spacing. Plantings spaced closer together will give you a faster visual impact, but you’ll need to divide bulbs more often. Plantings spaced further apart means you don’t have to divide as often, but it will take much longer to fill in the area.

Irises: Fertilization and Watering Practices

Fertilize your irises in early spring with a balanced, slow-release fertilizer. Avoid high-nitrogen fertilizers, as these can encourage leaf growth at the expense of flowers. We really like Espoma’s Bulb-tone for irises.

In San Antonio’s climate, irises benefit from a good watering schedule. Water deeply but infrequently, allowing the soil to dry out between waterings. Generally this means a good soak once a week, and twice a week when temps are hot and dry. This mimics their natural environment and helps prevent root rot. You can always test for soil moisture by poking a dowel into the soil to a depth of at least 3 inches. If soil sticks to the dowel and appears moist, skip watering; if soil flakes off, water.

Pest and Disease Management for Bearded Irises

Irises can be susceptible to pests such as aphids and iris borers. Regularly inspect your plants and use insecticidal soap or neem oil to manage infestations. To prevent disease, ensure good air circulation around your plants and remove dead or diseased foliage promptly. Watch for signs of fungal infections, such as leaf spot, and treat with a fungicide if necessary. Always remember that it will be important to refrain from spraying any products in the heat of the day during the hot temperatures of summer. And don’t forget to read your product label thoroughly and adhere to the application instructions.

Dividing and Preserving Irises

In general, you can plan to thin and divide irises every 3 years. The reason for dividing irises is to maintain vigor and prevent overcrowding and offer good air circulation throughout the plants to prevent disease. In San Antonio, the best time to divide irises is in late summer thru early fall.

Cut foliage back to about ⅓ of their full height. Carefully dig under the clump of irises, lifting the entire clump. You can now separate the individual rhizomes within the clump. Carefully look them over and choose what look like the strongest rhizomes. These healthy picks should have a small fan of leaves, a few inches of healthy looking rhizomes, and a number of well-developed roots. These newly dug up iris rhizomes can either be replanted right away or stored for later use.

If you need to dig up and store iris bulbs, clean them thoroughly by using a soft brush to remove soil, and let them dry in a shaded area. Once dry, store them in a cool, dry place with good air circulation until you’re ready to replant.

Have Fun with Bearded Iris Varieties

The ‘Bearded Iris,’ offers a bold, classic look with its ruffled petals and diverse color palette. You are sure to find a color combination that you fall in love with. If nothing else, the names some of these irises are given just might be what wins you over. ‘Jurassic Park’, ‘Red Hot Chili’, and ‘Apricot Kerfuffle’ just sound fun, don’t they?

Have a great time creating a stunning display of irises in your garden by choosing shorter varieties for the front of the bed, medium for the middle, and taller varieties in the back. see our blue informational signs displayed at the nursery for plant characteristics.

Irises make stunning cut arrangements in tall vases and receptacles, and with the necessity and ease of dividing irises, you can easily share rhizomes with fellow iris lovers. Maybe they’ll share some of theirs with you. I bet they will if you ask nicely!

We have a great selection irises at both of our Rainbow Gardens locations. Come pick out your favorites!

~The Happy Gardener, Lisa Mulroy