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The Top 10 Ways to Kill Plants You Love

March 19, 2012
Nanette Londeree

I’m a plant killer. Certainly, not intentionally. I’ve been gardening for decades and have grown thousands of plants – trees, shrubs, vines, perennials, succulents, edibles, houseplants, you name it. And though loathe to admit it, I’ve killed my fair share. Mind you, the plants I terminate are desirable ones, things I love and want to grow.  I don’t seem to have the same deadly luck with weeds, Bermuda grass or wild blackberries!  

Some of the fatalities, especially early in my horticultural endeavors, were largely from lack of knowledge. There wasn’t today’s bounty of readily accessible how-to information, so much learning came from trial and error. But there were plenty of senseless, avoidable losses. Over the course of my gardening lifetime, I’ve developed my “Top Ten Ways to Kill Plants You Love,” surefire practices that you should avoid.   

Number Ten - Forget the support
Many plants need something to cling to, wrap around or help stay upright. Without adequate support, the plants may not be able to maintain their own weight. For example, a tomato plant laden with hefty fruit broke off at the main stem because I used such a wimpy tomato cage.  Or the delicate foliage of a prized clematis broken at its base by busy squirrels (yes, squirrels!) before I trained the vine to a trellis.

Number Nine - Blow off protection
Planting everything in wire cages can be an effective deterrent to destructive gophers, but it’s a lot of work, and every now and then, plants have made it into the ground without it. When a plant is lying prone on the ground with absolutely no roots, like the gorgeous mature camellia at the peak of bloom, it’s clear the gophers got it. On a smaller scale, plenty of tender basil seedlings have vanished overnight when not adequately protected from marauding snails and slugs.

Number Eight – Over-zealous pruning
Generally we prune trees and woody shrubs to reduce size, eliminate damaged, diseased or dead material and shape them. If plants get out of control size-wise, then pruning may be more dramatic. But you can overdo it to a point where the plant may not be able to recover. Alas, that was my experience with a rambling rose that was about to topple a fence, and my pruning shears took off more than the “suggested” one-third of the plant. That rose is just a memory.

Number Seven – Slipshod planting
Giving your plants the best possible start in a new location begins by providing adequate drainage, healthy soil and planting at the right level (the root crown level with or slightly above surrounding soil). Planting too deep favors root and crown diseases, while planting too shallow can lead to root damage from exposure and excessive drying. A young magnolia tree was planted in an area where the drainage wasn’t optimum and with the top of the root ball at the soil level. Not having planned for settling, the tree ended up below grade where water collected, and yes, within a couple of years, the tree sadly succumbed to root rot.  

Number Six – Impulse buying
Have you ever walked into a nursery or home improvement store and been captivated by a beauty you knew nothing about, but just had to have? “I’ll find a place for it” you mutter to yourself because it’s just too pretty to pass up.  When you can’t find any cultural information on how to care for it, it gets plunked somewhere inappropriate, and ultimately kicks the bucket.  

Number Five – Lousy timing
I know not to plant tender seedlings or transplants until after the threat of frost, which, depending on your Marin microclimate, can be as late as the middle of May. But I just HAD to have those tomatoes in the ground for Easter (early April that year), and wouldn’t you know, one of those late season blasts from the arctic turned those little plants to black mush overnight!  

Number Four – Wrong plant, wrong place
You’ve heard about “right plant, right place”?  Making sure that the plants you choose are appropriate to the environment they’ll be growing in?  I didn’t heed it when designing a new garden and planting a dozen birch trees. They were growing all round Marin and listed in one of my garden reference books, so in they went. Fast forward a decade and nearly all were history. Our microclimate’s intense summer heat and limited water resulted in stressed trees that were prime targets for an insect pest that did them in. Had I known that a single tree can consume more than 200 gallons of water a day in high summer, I never would have planted them.  That was a hard (and expensive) lesson to learn.

Number Three – Bad choices
When shopping for trees and shrubs, bigger is not always better. Ideally you want a container-grown plant with a well-established root system, not a plant with a mass of roots circling near the outside surface of the container since that may prevent it from getting established once planted. But I couldn’t pass up that half-price tree in the “bargain corner” of the nursery. Once in the ground, it just languished – never really growing, and became yet another victim of insect pests.   

Number Two – Drying them or frying them
Plants need water, and one of the easiest ways to knock off your plants is not providing it when it’s needed. Ignoring symptoms of lack of water that some roses were exhibiting, it was too late when I found that the drip emitters for the plants were plugged, and the soil was bone dry.  Or the specimen shrub in a container that seemed to shrivel up before my eyes. It was diligently hand-watered every day and clear that water came out of the bottom of the pot. Turns out the plant was pot-bound; the root-ball had pulled away from the sides of the pot and all that water was running right down the outside of the root ball, never really getting to the plant’s roots.  

And the surefire, absolute  

Number One – Drowning them
Without a doubt the easiest, most efficient way to kill beloved plants. Plants need air in their roots to thrive; add too much water and you suffocate them. Excess water provides the perfect environment for root rot that can do in a plant very quickly. I’ve don’t this to way too many plants—whether indoors with orchids and African violets or outside with exquisite azaleas at the peak of bloom in decorative pots.  They start to look a little stressed, and you dump more water on them— that only speeds up their demise.

So whether you’re a garden newbie or a certified green thumb, you can avoid being a plant killer if you don’t use any of my top ten methods to kill plants—your garden will love you for it.  

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