Bearded Iris Bulbs Planting Tips

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Bearded iris bulbs are hardy exotic looking, long-lived flowering bulbs that bloom in the spring (April -June depending on the cultivar) and grow eight to twenty four inches tall.

The flowers have six petal; Three upright petals (called standards) and three hanging petals (called falls).

These delightful flowers are called "bearded" because of a fuzzy line or beard runs down the middle of each fall.

They come in an array of beautiful primary colors of blue and yellow, bi-colors like purple and white, and even pastel colors like pink.

What's especially nice is that now they come in a Reblooming variety which means you get to enjoy your bearded iris twice!

Most Reblooming Iris are tall and slender with multiple flowers per stem that bloom twice per season. Although the second flowering is not as spectacular as in the spring, it's still nice to have something wonderful like the iris blooming in your fall garden.

These come in a variety of colors such as the beautiful blue of the Victoria Falls which has great light blue ruffled petals on top of sturdy stems.

One of the most popular varieties of the Reblooming series is the 'Beverly Sills' with it's pale coral-pink petals.

Maybe you would rather have a pure white rebloomer. Then choose the 'Immortality' rebloomer from Holland Bulb Farms.

You may purchase these bearded rebloomers as well as other bearded iris at Holland Bulb Farms. Check out their internet specials now.

Buy your own bearded iris here.

How to Grow Bearded Iris

• Plant bearded iris bulbs in light shade to full sun. Tip: Too much shade will reduce or prevent flowering. On the other hand, the pink and blue varieties hold their color better with a little shade.
• Grow in fertile, well-drained, light loamy soil with a pH of 6 to 7 that has been amended with organic matter. Clay soil will need amending with pine bark and compost to keep rhizomes from being too wet.Tip: Manure is not recommended but can be used if well-rotted and incorporated to at least 6 inches deep into the bed. It's best not to let it come into contact with the rhizome.
• Bearded iris bulbs are hardy to zone 3. Some Louisiana iris grow as far south as zone 10.
• Iris are grown from divisions from thick, fleshy rhizomes (underground stems) that store food produced by the sword-shaped, semi-evergreen leaves.
• Rhizomes grow best when planted at or slightly below the soil surface with feeder roots penetrating the soil below.
• Offsets develop each year underground from the original rhizome producing a large fan of leaves and several flower stalks. Tip: Keep rhizomes firm and healthy by providing good drainage. Plant in raised bed of at least 6" or add a gravel mix like Stalite to your soil when planting.

• At planting, fertilize with a low-nitrogen fertilizer such as 5-10-10 incorporating per 50ft (1 1/2 oz per 10 ft)
• Keep watered before flowering in spring. Reblooming iris need to be watered during summer as well. The spring-flowering iris can tolerate drought.
• Once flowers fade, cut back flower stalks to an inch or two above the rhizome.
• Only fertilize if needed (if you have good green foliage, the plants will be fine). If you do fertilize, apply 1/2 cup of 5-10-10 fertilizer per iris clump after they flower around the rhizome (fertilizer may burn rhizome if applied directly).
• Divide after 3 to 5 years usually 4 to 6 weeks after flowering or in the fall. (See below on how to divide)

You will need a well-drained prepared bed. Dig a shallow hole just large enough for the rhizome or clump of rhizomes. Next, form a mound of soil in the center so that the top of the rhizome is slightly above soil level. Spread the roots over the mound and fill in with soil. Water well after planting.

Dividing Bearded Iris

Dig them up and cut the leaves to one-third their length. Wash off the soil and cut rhizomes apart so that each section has at least one healthy fan of leaves, and firm, white roots.

Older rhizomes of bearded iris bulbs should be discarded even, if they feel firm, because they will have little flowering ability.

Common Problems with Bearded Iris Bulbs

Bacterial soft rot This is the disease you definitely don't want! Bacteria enters the rhizome, usually through injuries or cuts, and causes the rhizome to become soft, mushy, and stinky. This can happen if you use fresh manure or excess nitrogen in addition to poor drainage. Definitely time to dig up and throw these rhizomes away and start over!

Crown rot fungus Not quite as bad as bacterial soft rot, since the plant can be salvaged. This fungus causes a rot at the base of leaves where they join the rhizome. This causes the leaves to fall over. You will also notice reddish-brown "mustard seeds" which are produced by the fungus. To correct, simply trim leaves to let more sunlight and air movement in to the rhizome. Be sure to remove and destroy diseased leaves.

Leaf SpotsOnce you iris has bloomed, it may develop dots on the leaves with small brown spots. Bacterial leaf spot has a watery, streaked appearance. Water-soaked margins around the spot turn yellow. Fungal leaf spots are rust-colored, drier, and more confined. Remove old foliage of infected plants in the fall so the disease won't overwinter. Spray with registered fungicide during extended periods of high humidity or rainy seasons.

Mosaic A viral disease that causes a mottling of leaves and flowers that is transmitted by aphids. Remove and destroy infected plants and control aphids.

Iris borer If you see small notches on the leaf edge or small accumulation of sawdust in early spring, spray with registered insecticide. If not treated, iris will develop loose, rotted bases and holes in the rhizome and bacterial rot may attack set in. Remove and destroy old leaves, stems, and plant debris in the fall.