Iris are one of the most hardy flowers we have here in the hot, dry plains of Oklahoma and definitely one of the prettiest when properly used in your landscaping plan. One of the beauties of growing iris is the constant production of new plants; if you have one you will have 10 before long. Splitting iris is just like splitting most bulbs, every two or three years it’s time to clean out the flower bed and open up room for new roots and new growth. Splitting needs to be done after the plant has been fully established in a bed for more than one year and only after the plant has finished blooming for that year. For iris this is usually mid to late July into the first of August. Splitting encourages blooming, and fuller, happier plants, as well as giving you something to take to the local plant swap, or give away to friends. You’ll need a good pair of scissors and a small bucket of cleansing mix with 1 part bleach to 10 parts water.
Now grab your shovel and lets get dirty!
Step One: Dig under the bulb usually staying about 1 foot away from the base of the iris bunch you are planning to split. Let the shovel lift the bulbs from the dirt and then reach in with your fingers and pull the bulbs out. You can inspect the bulb for rot and break or cut off any that you find. Look for new growth which usually forms as a little bubble on the side of the bulb (top right image). Any bulb with bubbles is usually healthy and will produce new plants. You can find all the spurs with green leaves and break those off making individual plants out of each one. That is the process of splitting. See isn’t it easy?!
Step Two: After splitting all the bulbs now comes the cleansing and cutting process. Trimming a plant back is always a good way to give it a head start on the next season. This is no different with iris. Splitting the bulbs eliminates root stock by cutting the plant back and giving it time to produce new fresh roots and catch up to it’s top growth. This technique ensuring a more healthy plant with a stronger start in the spring. To cut an iris back I use a basic rule of thumb; ‘nine inches and new growth’. I leave approximately nine inches of green foliage and cut the rest away, except where new growth is concerned. New growth shows up as smaller, darker green blades of foliage similar to the larger parent blades. I always leave these blades even if it’s longer than nine inches. The image on the above left shows my fingers marking a cut path around the new growth. Notice the smaller blade separating from the side of the parent. That’s new growth and should be left to develop.
Now that you’ve got all of your bulbs cut you’re ready to cleans and transplant.
Step Three: Cleansing is simply a means by which I ensure no unhealthy fungus or bacteria have attached themselves to the iris bulbs. It’s also a good way to clean your gardening gloves…as long as you want them white. Remember the mixture of 1 part bleach to 10 parts water I told you about in the beginning? Well, here is where that comes in…take each bulb and thoroughly douse it in the bleach/water mixture. Swish it around a bit until you are sure it’s good and covered. Toss the cleansed bulbs in an old paper grocery sack or old cardboard box until you are ready to re-plant.
Step Four: If you’re not ready to plant immediately wrap the cleansed bulbs in newspaper or a paper sack and keep them in a dark, cool, dry space until you are ready to plant. The best time of course is to plant immediately after splitting giving them time to put down roots and begin to established themselves before winter sets in. If you don’t have a place for them ready, store them until spring and they will be right there waiting for you.
A few other tips about keeping iris: first, they will grow anywhere but they prefer full sun to partial shade, depending on the variety. They will take about as much water as you can give them but standing water is bad, bulbs can rot pretty fast so try not to plant them in a hole or at the bottom of a depression in the ground. Iris look their best in groups and as a colorful background. I love to see them layered with Canna’s and lower growing ground covers like sweet potato vine and annuals. They look great around trees and along fence rows, they just tend to stand out in rows. Iris are one of my favorite flowers. I don’t know if it’s their ease of keep, or just the fact that they have such a beautiful variety of colors and styles; whatever it is, I love planting iris and I hope you can enjoy this easy-keep beauty yourself.
From the Farm
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