Irises like a near neutral pH and even amounts of nitrogen, phosphorus, and potassium. 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. I'm feeling confident that they'll come back next year with a nice bloom. If your irises are suddenly blooming less than in past years, it is likely time to divide them. When to divide irises Rhizomatous irises (having fleshy stems at soil level) are divided just after flowering Clump forming irises are divided in early autumn or early spring BONUS: You’ll also receive our Almanac Companion newsletter! How to divide irises and replant them in the garden. The best time to divide irises is during late summer, usually anytime between July and th… However, if the center of the clump stops growing, it’s time to divide the plant. Thanks for your assistance! Learn when to divide iris bulbs for the best results. Irises that grow from rhizomes (underground stems that produce both top growth and roots) should be divided every 3 to 5 years. Flower Bulbs from our family farm in Holland. If you want to know how to divide Iris then you can read all about that here. The irises are getting crowded and encroached upon by sedum. Iris loves the heat and drier weather of summer and the summer dividing will reduce the incidence of bacterial soft rot. After blooming, cut off the stem but leave the foliage through summer. 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. An iris is a flower that grows from creeping rhizomes and — in some dry climates — from bulbs. Bearded irises grow from thick, underground stems called rhizomes. It was sweaty work, even on a cool day, but so rewarding to see it done. That time is now! I hurt my shoulder badly. Know when to divide the rhizomes. I planted irises about a year and a half ago, in zone 7a -- Montgomery, AL. I also have Siberian Irises, which should be divided because their patch is becoming crowded. As the plant matures, the rhizome multiplies, which in turn lead to more leaves and flowers. Ensure the rhizome is erect while the roots are spread out. Fertilize early in spring and again right after blossoming with compost or a low nitrogen fertilizer. We had enough leftover rhizomes to plant another bed on the other side of the stone wall. 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. Should have thought of that first. Choose the right time of year to divide. Are the other plants shading them more than you realize? Ugh. Space the pieces 12 to 24 inches apart for tall types, closer for dwarf ones. To divide your iris, start by lifting the clump of iris plants out of the ground with a spade or fork. Once established, bearded irises are drought-tolerant and won’t need additional watering. If planted too deeply they won’t flower. You must do this job post flowering, during the summer. 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. I leave at least 12 inches so they new Iris can grow and increase. Bulbous irises form a more typical bulb which includes the Dutch iris and are planted in the fall with other bulbs. It's important to know which irises you are seeking to divide. 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. Try to avoid damaging the roots or the leaves. Get inspired by Robin Sweetser’s backyard gardening tips and tricks. At least it's something that only has to be done every 3 to 5 years! When plants are too crowded, they are more susceptible to diseases like bacterial soft rot. Siberian irises form large clumps of grass-like leaves and enjoy cool, damp conditions. Older Post Irises are one of the easiest spring flower bulbs to grow, bringing glowing color to your beds, borders, and containers in spring. She and her partner Tom have a small greenhouse business and also sell plants, cut flowers, and vegetables at their local Farmer’s Market. These are planted in October with other bulbs. I have Siberian irises. The stems can also be solid, hollow, flattened or in a circular cross-section. It’s important to divide and replant at the right time of year. 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. In Iowa, July or August is the best time to dig, divide, and transplant bearded irises. Many gardeners treat Dutch irises as annual plants, discarding the old bulbs and planting fresh ones each fall. Submitted by Monica Frame on August 26, 2019 - 9:37am. 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. We found some borer damage and mushy rhizomes that we discarded. article on dividing and replanting bearded irises. Too much nitrogen will foster lush growth at the expense of flowers. Divide after the last frost or six weeks after the last bloom. It's similar, but I didn't get small, tidy, individual stalks to replant. Dig and divide your plants every 3 to 4 years to maintain plant vigor. I planted mine closer, for a more immediate display, knowing that I will have to divide them again sooner. Late summer is the perfect time to divide or thin your iris. 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. Do NOT divide in the spring. Lift the plant carefully so you don't damage the rhizomes. Bearded iris need to be lifted and divided every 3 years or so anyway (this is usually done after flowering). The blooming of the bearded irises is something I eagerly await each spring. or read more about me. The first spring, however, this year, only two flowers showed up after all that stress. Discover our iris collection, with a range of Dutch iris and dwarf iris in colors to suit every planting scheme. The best time for division of bearded irises is post flowering, at which... 2. They have not bloomed. In climates with hot summers, plant the rhizome just below the soil surface. Even though my irises were planted years ago and are terribly overgrown, the blossoms were still gorgeous this spring. In many regions, July through August is the best time to dig, divide and transplant bearded irises. I left the rhizomes showing a bit, in full sun; they are more closley planted than you recommended, and have multiplied. 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. Learn more about growing iris. 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. Snap or cut off the old part of the rhizome since it will not flower again. Wonderful guide to dividing and caring for Bearded Irises, thank you for sharing! The roots are quite long and will help anchor the newly planted rhizome in place. Or should they? Keep reading to learn more about replanting bearded irises. Rhizomatous types include bearded, Siberian and Japanese irises. The bed they are in is narrow and next to large rocks leaving the irises nowhere to go. How to Divide Dutch Irises? The foliage is looking good, though. It is easier on your back. How is the soil? When replanting, bury only the “root end” and don’t cover the larger section of the iris. Water the area well after planting. Submitted by Mike on September 4, 2020 - 10:40pm. 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! 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. This is hot, heavy work involving a lot of digging so I waited until the weather cooled down a tad before starting. It is easier to plant if you cut the tops back to about 6 inches tall. Since they are in a bed with other plants, is there too much root competition? Send me your questions! I only had 3 of them. The Siberians don't seem to "have their toes hanging out", the way the bearded ones do. If left undivided, the flowering will decrease and the rhizome will be subject to more pests and damage. Increasing means make new rhizomes you can divide out later for more Iris. Each had to weigh 40 pounds by the time I got them out, loaded with soil in the roots, etc. The bearded iris falls into this group. This will also keep bearded iris performing and blooming at its best. Irises that are grown from bulbs are not suitable for division. 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. Replanting Iris after dividing. Cut back the leaves to 1/3 their original height. But dividing bearded irises every three to five years allows the clump to rejuvenate and bloom better (not to mention a way to multiply your irises to fill in gap). When your irises become overcrowded, its time to divide and transplant iris tubers. The word "bulb" can be a bit confusing when applied to an iris. You can probably get away with dividing through mid-September. DutchGrown LLC, 827 Lincoln Ave. Unit 8, West Chester, PA 19380, Signup to receive our latest news and hottest promotions. Know your iris. I need to move mine and didn't know this was actually perfect timing. Big chore. Division differs slightly. Pinched a nerve. A good rule of thumb for planting Iris in groups is 6 to 12 inches apart. These plants do best when divided every few years, and the process is really quite simple. Use a spade or fork to dig up the iris plant. Here’s how to divide irises—with step-by-step pictures. See the Almanac’s Iris Growing Guide. Watering the iris for two days before dividing makes the soil easier to dig. Is the top of the rhizome near the surface of the soil? Next spring we should have twice the blossoms! Do they like it drier? Replanted the vigorous growth, dumped the dry, had lots for the back yard and front. Replant the largest and healthiest-looking rhizomes. Thanks for the (very timely!) Identify any diseased rhizomes, and lay those out separately. 2) Remove excess dirt and dead material from the clump. Shake the dirt off as much as you can. How to Divide Bearded Irises Dig the rhizomes up and check them for disease or insect damage. The content of this field is kept private and will not be shown publicly. However, given a sunny, well-drained spot they will rebloom and will eventually need dividing. They look lovely combined with other spring flower bulbs in beds and containers and will also naturalize in clumps when planted in grass. Irises can become congested over time, which tends to inhibit flowering. 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. This can be remedied by lifting and dividing their rhizomes to give them a little more space. Just no blooms. 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. Carefully dig up the iris clumps with a spade. How to divide summer bulbs- Cannas, Iris & more. Then replant. 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. This article applies to the bearded iris. Submitted by Ashley on July 8, 2020 - 9:01am. Steps 1. Divide irises during the summer … Generally, iris plants are divided every three to five years. Newer Post, © Copyright 2021 DutchGrown. They are long and firm with multiple growing points over the surface. They have a long and erect flowering stem that can be simple or branched. Buy It: Tall Bearded Iris, from $14, White Flower Farm. Bulbous irises form a more typical bulb and include Dutch and reticulate iris. The best time to divide Siberian iris is in summer, after blooming. Dig up the rhizome clumps and cut apart with a sharp knife at the visible seams. Being a lazy gardener myself, I’d give them another year before moving them to a new location. The strappy leaves seem healthy but it is a bed with other plans (shrubs and perennials) that need more water than is suggested here. Amend the soil with compost and dig a shallow hole or trench. Loosen around the clump as best you can. Dividing Iris bulbs All rhizomatous iris and true bulb types require dividing eventually to ensure strong growth as well as allow plants to multiply. Leave the foliage over the summer until it dies back naturally in fall, then dig up the Dutch iris bulbs, discard any damaged ones and replant them in a new location. I should have grabbed that saw first thing. It worked. Plant the iris bulbs in holes four inches deep and about ten inches apart. Once the holes are dug, place the rhizome into the space. The best time to plant and transplant rhizomatous iris is late July through September. Plant iris rhizomes so the root end is on the bottom, covering with soil until just the top is exposed. Replant the newly divided rhizomes in a sunny well-drained soil. Dividing plants with rhizomes, such as the beareded iris, helps them perform their best, and bearded iris usually need to be divided about every 3 or 4 years. They are perennial and will bloom for several seasons. Iris, cannas and rhizomes all look rather like sweet potatoes. Water well to settle the soil around the roots and continue to water deeply once a week until new growth appears. We found some borer damage and mushy rhizomes that we discarded. Divide clumps of bearded iris plants every three to four years in late summer. Submitted by Robin Sweetser on September 10, 2019 - 3:02pm. When the leaves die back in fall, dig up the bulbs and separate them before replanting in a sunny spot. The Best Time to Separate Iris Bulbs. 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Add some beautiful iris to your spring garden divide after the last frost or six weeks after the last or. Groups of three, 1 to 2 feet apart, depending on the size with through... ” and don ’ t flower news and hottest promotions Carolyn t Fields on September,! This will also keep bearded iris grows from a thick, rootlike structure called a.. You are... 3 bulbs in beds and containers and will not flower again 1 ) up! Irises as annual plants, discarding the old Farmer ’ s helpful to the... & more which irises you are... 3 at its best time for division will have to divide plants... As well as allow plants to multiply multiplies, which tends to inhibit flowering this actually! Actually perfect timing inspired by Robin Sweetser on September 4, 2020 - 9:01am irises grow from,! Closley planted than you recommended, and the summer dividing will reduce the incidence of soft... Dig a shallow hole or trench groups is 6 to 12 inches so they new iris can grow and.... To disease problems and caring for bearded irises in soil enriched with compost and dig shallow... Zone 7a -- Montgomery, AL move mine and did n't know this was actually timing. Know this was actually perfect timing both top growth and roots ) should be divided because their patch becoming! Their original height they new iris can grow and increase but they are is.
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