Tag Archives: pruning


Large bunch grasses can be among the most challenging plants to prune. Every year they send up dozens of flowering stalks, which quickly turn into seed-heads shedding vast numbers of tiny potential grass sprouts all over the nearby landscape. Many gardeners resort to heavy weaponry to simply shear them right down to the ground, leaving behind an ugly, unhealthy, flat-topped “tuffet” of cut stems and leaves. Definitely not naturalistic!

I was recently faced with just such a challenge. Large clumps of perennial grass had gone to seed and grown out into unruly pompoms with long leaves (blades) trailing out across nearby plants. The client agreed that another annual shearing was not wanted, but could these grasses be limited back without sacrificing a natural look?

Of course they could! But it involved three different pruning methods, two of which were invented on the spot. Let’s start in the back garden, where a large grass looked like this in the “before” picture:


First, the seed stems. They all had to come off. I reached in and clipped the seed stems way down among last year’s sheared-off stems. That worked to invisibly remove them, but there was a problem: I was also removing a lot of the green blades clinging to the stems. This was not good because those leaves made up about a third of the overall density. I was thinning too much!

I invented a new method just for this kind of grassy seed heads, clipping about half way up each stem, just a tiny bit above the node where the largest live blade was attached. Most of those blades were left in place, and the overall density was preserved. I call this new style of pruning “partial grass deadheading” because it leaves the lower half of the seed stalks in place while removing the business ends.

The second kind of pruning was also brand new. Unlike the leaves of broadleaf plants, grass blades elongate as they grow. This is an adaptation to herbivores that bite off the ends of the blades. Such shortened blades can still grow longer. But there are no grass-eating herbivores in most suburban gardens, and the blades of the bunch grasses tend to grow longer and longer. I realized that for these grasses to be trimmed in a healthy way I had to become that herbivore.

Having recently experienced a haircut, I realized that I could use a method similar to what my friend Janice had done to my head. I swept my hand across the ends of the over-long blades, scooping up a manageable handful and gently tugging outward. Then I clipped off the ends of all the blades in that handful, depositing the cut off bits into the debris bin. By repeating this operation all around the outer parts of the clump, I was able to reduce the lengths of the blades without creating a sheared off look. I call this pruning method “bunch grass haircut pruning.”

With the seed heads gone and the blades shortened all around, the bunch already looked much better. But the overall size of the bunch was too large and there were lots of old blades and stems around the base. It needed to be smaller without sacrificing the naturalistic look. I used a variant of undercut pruning. Reaching deep under at the base, I grabbed a small tuft and clipped it right at ground level, repeating and carefully observing the results all around the base of the plant. The density near the base was reduced, creating more of a fountain appearance and less of a pop-pom.

Here is the result on the bunch grass in the “before” picture above. Notice how much more visible are the small silvery plants near the base:


Out in front of the house at the base of a tree, there are three more clumps of the same grass. Applying the same three pruning methods, these clumps were rapidly tamed. There is a “before” picture at the top of this post; here is another:


Let’s have a closer look at the rightmost clump before pruning. See how dense are the seed stems, and how long the blades:


This is how these grasses looked after the pruning. What do you think?


I love pruning as much as I love creating deep nature gardens. I am available to prune almost anything in your garden (except mature trees, for which we bring in a licensed tree surgeon). If you are not near us, I am also available through online media (email or real-time video) to coach you on how to prune your plants.

Look at this monster! It’s like a gigantic plant amoeba, slowly oozing out across the landscape. Beautiful in its own way but just a bit too aggressive. Let’s see if we can tame it.

Here is a basic principle of ecosystem gardening: even though the garden is managed by a human, we want it to have a natural look, as if all the plants sprouted and grew right where they are. So the challenge in pruning is to make the resulting pruned plant look like it has not been pruned. Can it be done here? Let’s find out…

For this task, I’ll be using a method I call “edge undercut” pruning. The idea is that we want the plant to look as natural as possible, through the entire pruning process.

Edge undercut is accomplished by reaching in under the lowermost, outer edge of the plant and clipping as far as possible in the depths of the stems. The primary factor is whether or not the cut ends of the stems are visible. A secondary factor is whether there is an obvious notch or gap in the plant’s overall shape.

With sturdy shears in hand, I began with round 1. It took about 15 minutes. All around the outer edge, just a few stems at a time, frequently stepping back for a look. This is art, people!

Here’s how it looked after round 1. See how it still looks fairly natural. All I’ve done is elevate the lower edge a bit, giving the whole plant a smaller “footprint”:

…and here is the pile of clippings at this point:

The clippings will be added to the compost pile, which has just been started at the back of the yard.

I’m not done yet! The bush is smaller, but it still takes up too much space. For round 2, I have to start watching the flower balance. The bees LOVE the lavender flowers, so I want to be careful to keep as many as possible. Fortunately, the flowers are mostly on the upper section of the bush.

Around once more, this time clipping into the actual main mass of the bush, still stepping back frequently for an artistic evaluation. Here is how it looks after round 2:

It’s definitely smaller. I have not yet decided whether to remove the catnip plant on the right side. It’s the only medium size catnip left in the garden, but it’s a bit bedraggled.

I’ve clipped much more off on the east side (the far side of the picture above), giving the bush a bit of a “windswept” look and making more room for new plantings on that side. The main stems are now visible (but still no obvious cut stem ends!) and the open space created there will fill in over the next few months as the lavender bush adjusts itself, growing out new shoots to meet the light:

…and here is the second pile of clippings, more compost food:

Thanks to careful pruning, the giant lavender monster is now tamer, and the bees still have a bounteous source of nectar and pollen:

This post is part of the new ecogarden project at Elizabeth’s place

also part of this project:

putting in a redwood walkway

in the company of chickens

Your comments are welcome!