If you are a regular or even occasional visitor to the Garden, chances are that you've seen the colorful and eye-catching display of either Siberian or Japanese Iris that take center stage in late spring and early summer. This year, the Siberian Iris were simply magnificent and demand for starts unprecedented, which tells me that there are quite a few new Iris gardeners out there who would probably appreciate some pointers on cultivation. Generally speaking, beardless Iris are relatively easy to grow and will bloom reliably with at least a half day of sun, fairly decent soil and plenty of water (an inch a week, just like your lawn) throughout the growing season and particularly for those new transplants. Drought and starvation usually will not kill an established clump of Siberian Iris, but I don't recommend it, especially not for Japanese Iris, which can be a bit prima-donna-ish.
Assuming you have grown your new plant successfully over the summer, it's had a couple of gorgeous early blooms because you grabbed the one that actually had buds on it and you are now looking forward to some impressive growth and bloom next year. You should be aware that fairly soon your plant will appear to be a bit peaked with yellowing leaves that will start to turn brown as September transitions into October. Don't freak out, it's fine, you haven't killed your Iris because it's a perennial and just going dormant for the coming winter months.
So now it's October and you have a mass of dead brown mushy leaves perhaps punctuated by a few rather defiant dark russet seed pods and your wondering how to proceed. You actually do have options and hindsight is a great thing. First off you should have chopped off those seed pods before they fruited, in fact right after flowering for maximum benefit, thereby allowing all the energy to go into producing new roots, shoots, etc. Oh well, better late than never. So grab your pruners, shears, whatever and go for it, chopping down the entire thing and being sure to leave about three inches or so of stubble at the base of the plant. Avoid damaging the new shoots which may already be emerging because we live on the coast and the climate is bonkers. If the plant in question is a Japanese Iris however, you can take the entire thing off at the ground, leaving a pristine patch of virgin soil that would delight the soul of any neat freak.
I mentioned options and neat freaks, so here are some variations on the theme. It all depends on your priorities as a gardener. Once those leaves begin to turn yellow they are not going to photosynthesize as effectively as green leaves. Of course they won't all turn yellow at the same time, but they just look so tacky. They might get wet and yucky and mildew if it rains so why not just cut them off right now and be done with it? Seed pods, what seed pods? Done! Or.... leave everything alone and look at the colors of the foliage as the September sun lights it up, saffron, amber and rust. Listen to the rustling of the drying leaves as the winds sift through them. Then when Fall is over and the plant finally succumbs to the October rain, you cut off the dead foliage and enjoy taking a glimpse of the ecosystem at work beneath the base of the plant, recycling the spent material, oblivious to the world above. You leave the seed pods, sentinels in the autumn mist to catch the filigree webs of busy spiders and bring the sparkle of diamond dew drops to the early morning garden.
Your call or choice: Neat Freak..... or.... Earth Mother........ What kind of gardener are you?