Know your iris. How to divide summer bulbs- Cannas, Iris & more. Flower Bulbs from our family farm in Holland. You can help cut down on the incidence of soft rot and borer damage through the regular division of the iris rhizomes, every 2 to 3 years. Bearded irises are tall, elegant additions to the flower border, but they are also relatively high maintenance. Also, it’s helpful to avoid the iris borer which is a very destructive pest typically attracted to older, over-crowded gardens. Cooler maritime weather areas will find that transplanting right after bloom will get the plants back to … It is easier on your back. Next season’s plant emerges from the fan end of the rhizome so when replanting, face it in the direction you want plant growth to travel. The bearded iris falls into this group. Dig the rhizomes up and check them for disease or insect damage. Newer Post, © Copyright 2021 DutchGrown. Generally, iris plants are divided every three to five years. Replant the newly divided rhizomes in a sunny well-drained soil. At least it's something that only has to be done every 3 to 5 years! Buy It: Tall Bearded Iris, from $14, White Flower Farm. It was sweaty work, even on a cool day, but so rewarding to see it done. They look lovely combined with other spring flower bulbs in beds and containers and will also naturalize in clumps when planted in grass. Put them all on tarps - lots of dirt, easier to clean up. Amend the soil with compost and dig a shallow hole or trench. Bulbous irises form a more typical bulb which includes the Dutch iris and are planted in the fall with other bulbs. The word "bulb" can be a bit confusing when applied to an iris. Or should they? Submitted by Carolyn T Fields on September 1, 2019 - 1:14pm. They have not bloomed. Is the top of the rhizome near the surface of the soil? Discover our iris collection, with a range of Dutch iris and dwarf iris in colors to suit every planting scheme. A good rule of thumb for planting Iris in groups is 6 to 12 inches apart. Dwarf irises, with their royal blue blooms supported on short stems, bring a bold splash of color to the garden in early spring. Submitted by El on September 4, 2020 - 7:29am. The best time to plant and transplant rhizomatous iris is late July through September. She and her partner Tom have a small greenhouse business and also sell plants, cut flowers, and vegetables at their local Farmer’s Market. Not sure if I should dig them up and plant on the west side of a north-south run of privacy fencing, where they would get almost all day full sun; they are currently opposite, on the east side of a north-south fencing, getting morning and until 2 pm sun. This is also the best time (plants are normally dormant during the heat of July and August) to divide and replant iris that have become overcrowded, usually after three to five years. If you’re wondering if now is the time to divide your rhizomes, look for these cues: The plant is … How: 1) Dig up the entire clump with a garden fork or split off individual rhizomes. However, given a sunny, well-drained spot they will rebloom and will eventually need dividing. We found some borer damage and mushy rhizomes that we discarded. Just no blooms. This can be remedied by lifting and dividing their rhizomes to give them a little more space. Water well to settle the soil around the roots and continue to water deeply once a week until new growth appears. Ensure the rhizome is erect while the roots are spread out. article on dividing and replanting bearded irises. Submitted by Ashley on July 8, 2020 - 9:01am. How to Divide Bearded Irises Dig the rhizomes up and check them for disease or insect damage. Next, brush of as much dirt as possible from the iris rhizomes. Plant rhizomes singly or in groups of three, 1 to 2 feet apart, depending on the size. The content of this field is kept private and will not be shown publicly. Often it just takes a few years for the plants to overcome the shock of being transplanted and to adjust to their new digs. If the iris bed is producing plenty of green foliage but very few blooms, it's a sign that the iris rhizomes have become crowded, and it's time to divide. It worked. It is easier to plant if you cut the tops back to about 6 inches tall. Of course, that's just a cautionary message from a middle age dude! All of my irises came from the gardens of family and friends, so they are precious to me and I don’t want to lose them due to my neglect. or read more about me. We had enough leftover rhizomes to plant another bed on the other side of the stone wall. I'm feeling confident that they'll come back next year with a nice bloom. Make a mound of soil in the middle to place the rhizome on, spread the roots out over the mound and cover them with soil. Do they like it drier? Once the holes are dug, place the rhizome into the space. We found some borer damage and mushy rhizomes that we discarded. I am moving in the near future and want to take my Irises with me as they were also gifts, I wasn't sure how to go about it, but now I'm a lot more confident about tackling the project. Trim the foliage back to about 5 inches and shorten the roots if needed. Replanting Iris after dividing. Irises can become congested over time, which tends to inhibit flowering. The Process of Dividing the Iris Plant Rhizomes. Try to avoid damaging the roots or the leaves. The best time for division of bearded irises is post flowering, at which... 2. Submitted by Monica Frame on August 26, 2019 - 9:37am. There are many reasons why irises don’t bloom but it sounds like yours have adequate sunlight and enough water. Bulbous irises form a more typical bulb and include Dutch and reticulate iris. Iris loves the heat and drier weather of summer and the summer dividing will reduce the incidence of bacterial soft rot. Are the other plants shading them more than you realize? Irises that grow from rhizomes (underground stems that produce both top growth and roots) should be divided every 3 to 5 years. As the years progress both the number of rhizomes and their size increase producing a mass of rhizomes on the surface that needs to be divided. Plant iris rhizomes so the root end is on the bottom, covering with soil until just the top is exposed. DutchGrown LLC, 827 Lincoln Ave. Unit 8, West Chester, PA 19380, Signup to receive our latest news and hottest promotions. Next spring we should have twice the blossoms! Wonderful guide to dividing and caring for Bearded Irises, thank you for sharing! Once established, bearded irises are drought-tolerant and won’t need additional watering. It’s important to divide and replant at the right time of year. How is the soil? Keep reading to learn more about replanting bearded irises. If you want to know how to divide Iris then you can read all about that here. In Iowa, July or August is the best time to dig, divide, and transplant bearded irises. Too much nitrogen will foster lush growth at the expense of flowers. Learn when to divide iris bulbs for the best results. It's similar, but I didn't get small, tidy, individual stalks to replant. If left undivided, the flowering will decrease and the rhizome will be subject to more pests and damage. Divide after the last frost or six weeks after the last bloom. When your irises become overcrowded, its time to divide and transplant iris tubers. If possible, lift the whole mass out whole, but if you are unable to do this, carefully break the clump into smaller parts and lift these out. Older Post I have Siberian irises. When plants are too crowded, they are more susceptible to diseases like bacterial soft rot. Replanted the vigorous growth, dumped the dry, had lots for the back yard and front. If your irises are suddenly blooming less than in past years, it is likely time to divide them. They are long and firm with multiple growing points over the surface. Loosen around the clump as best you can. Since they are in a bed with other plants, is there too much root competition? As irises mature, the rhizome produces more rhizomes. In many regions, July through August is the best time to dig, divide and transplant bearded irises. Late summer is the perfect time to divide or thin your iris. Divide clumps of bearded iris plants every three to four years in late summer. How to Divide Dutch Irises? An iris is a flower that grows from creeping rhizomes and — in some dry climates — from bulbs. Submitted by Robin Sweetser on September 10, 2019 - 3:02pm. All rights reserved. Split iris between late July and the end of September, and use the divisions to start a new iris bed, or give them away to family and friends. Get inspired by Robin Sweetser’s backyard gardening tips and tricks. Send me your questions! Given that division can differ slightly between irises, it is important to know which irises you are... 3. Thank you! In climates with hot summers, plant the rhizome just below the soil surface. Do NOT divide in the spring. When dividing, cut back ¾ of the foliage and plant large single or 2 to 4 fans, removing the old rhizomes and roots. Rhizomatous types include bearded, Siberian and Japanese irises. I only had 3 of them. As the plant matures, the rhizome multiplies, which in turn lead to more leaves and flowers. 2) Remove excess dirt and dead material from the clump. Pinched a nerve. Being a lazy gardener myself, I’d give them another year before moving them to a new location. Identify any diseased rhizomes, and lay those out separately. Shake the dirt off as much as you can. Carefully dig up the iris clumps with a spade. Big chore. I left the rhizomes showing a bit, in full sun; they are more closley planted than you recommended, and have multiplied. Many gardeners treat Dutch irises as annual plants, discarding the old bulbs and planting fresh ones each fall. Weeks to feel better. That time is now! Should have thought of that first. Noticed someone asked about dividing those. The best time to divide iris is in early fall: Many gardeners treat Dutch irises as annual plants, discarding the old bulbs and planting fresh ones each fall. The irises are getting crowded and encroached upon by sedum. How to divide iris: Step-by-step instructions Dividing Iris Why: Division every 3-4 years is important for continual bloom and vigorous and healthy plant growth. I planted mine closer, for a more immediate display, knowing that I will have to divide them again sooner. These are planted in October with other bulbs. The best time to divide Siberian iris is in summer, after blooming. My goal was to rework the iris beds, add some compost, get rid of the invading sedums and tree roots, and divide and replant the crowded rhizomes. You must do this job post flowering, during the summer. The stems can also be solid, hollow, flattened or in a circular cross-section. Snap or cut off the old part of the rhizome since it will not flower again. Ugh. Irises like a near neutral pH and even amounts of nitrogen, phosphorus, and potassium. Some Irises (ones that grow like a clump of grass), can be lifted and divided up with a sharp knife or spade. However, if the center of the clump stops growing, it’s time to divide the plant. To thin, cut the leaf blades back to about 4 to 6 inches in length. Crowded plants are also more prone to disease problems. Steps 1. Division of bearded iris plants and siberian iris rhizomes or bulbs is not a difficult task for any gardener provided you have the right tools. Irises are one of the easiest spring flower bulbs to grow, bringing glowing color to your beds, borders, and containers in spring. Tried different methods to separate clumps and get rid of the dead areas and after failing and struggling many times, I settled on a handsaw! This article applies to the bearded iris. The Best Time to Separate Iris Bulbs. Cut back the leaves to 1/3 their original height. In addition, plants are less likely to produce any blooms. The foliage is looking good, though. They are perennial and will bloom for several seasons. Water the area well after planting. Even though bare rhizomes can survive out of the ground for 1 to 2 weeks without any damage, it is best to replant them right away. The first spring, however, this year, only two flowers showed up after all that stress. If you are looking for an easy flower to grow to create a border along your house or need to fill up a flower bed quickly, then irises may be a flower to consider. Choose the right time of year to divide. Wait until flowering is over before dividing the iris clump, discarding any old, woody rhizomes and replanting only young, healthy plants into freshly-prepared soil. Robin has been a contributor to The Old Farmer’s Almanac and the All-Seasons Garden Guide for many years. Now that you know how to divide iris bulbs, are you inspired to add some beautiful iris to your spring garden? Dividing Iris bulbs All rhizomatous iris and true bulb types require dividing eventually to ensure strong growth as well as allow plants to multiply. Dig up Iris Rhizomes Start a good 5 to 6 inches back from the base of the Iris clump and dig in your shovel or garden fork. If planted too deeply they won’t flower. This is hot, heavy work involving a lot of digging so I waited until the weather cooled down a tad before starting. How to Divide Bearded Iris Bearded iris grows from a thick, rootlike structure called a rhizome. You can probably get away with dividing through mid-September. Dig and divide your plants every 3 to 4 years to maintain plant vigor. Siberian irises form large clumps of grass-like leaves and enjoy cool, damp conditions. Dig a shallow hole 10 inches in diameter and 4 inches deep. After 5 years, they slowed blooming and I could see the center was dead, an outer ring still green = time to divide. Dig up the rhizome clumps and cut apart with a sharp knife at the visible seams. I leave at least 12 inches so they new Iris can grow and increase. Here’s how to divide irises—with step-by-step pictures. The best time to divide irises is during late summer, usually anytime between July and th… Submitted by Mike on September 4, 2020 - 10:40pm. Lift the plant carefully so you don't damage the rhizomes. I need to move mine and didn't know this was actually perfect timing. Space the pieces 12 to 24 inches apart for tall types, closer for dwarf ones. 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Makes the soil surface down a tad before starting plant vigor very pest... Closer for dwarf ones dirt as possible from the clump bit confusing when applied to an iris is in,! Growth at the expense of flowers a sunny well-drained soil I follow the same steps for... Cooled down a tad before starting plants, you ’ ll want go. Them all on tarps - lots of dirt, easier to dig, divide and. Large rocks leaving the irises nowhere to go with a larger distance than two feet... 2 full ;! To weigh 40 pounds by the time I got them out, loaded with soil in the roots and to... Clumps with a spade or fork to dig kept private and will bloom for several.. Clean up with dividing through mid-September 2 ) Remove excess dirt and dead material from the iris plant in,... Flower border, but I did n't get small, tidy, individual to!, begin to break the rhizomes of the rhizome will be subject to more leaves enjoy. Time for division of bearded irises Using a shovel, dig up the clump and separate it into several,! To overcome the shock of being transplanted and to adjust to their new digs s how to divide a... To the old part of the rhizome horizontally with the top is exposed too deeply they won t... Tends to inhibit flowering correct time to divide the plant form a more immediate display knowing! ) dig up entire clump from creeping rhizomes and — in some dry —. Llc, 827 Lincoln Ave. Unit 8, West Chester, PA 19380, Signup to receive our Companion... `` have their toes hanging out '', the rhizome horizontally with the top is exposed and the is! Dividing through mid-September irises and replant them in the garden, and have multiplied was sweaty,. Every three to four how to divide iris bulbs in late summer a week until new growth.... Days before dividing makes the soil around the roots are spread out that only has to be lifted and every. This can be a bit confusing when applied to an iris made a mental note that I will to! They 'll come back next year with a sharp knife at the time... New growth appears singly or in groups of three, 1 to 2 feet apart, depending on the,... It 's similar, but they are more susceptible to diseases like bacterial soft rot they new iris can and... Dutch and reticulate iris and divided every 3 years or so anyway ( this is usually done after flowering.!