Garden myths uprooted
Nov./Dec. 2015 California Bountiful magazine
By Pat Rubin
The truth behind gardening advice
Myth: Dig a $50 hole for a $5 plant.
Uprooted: Actually this "myth" can go either way. Most nursery staff tell you to throw the best of everything—compost, rich soil, time-release fertilizer, nutrients your soil may be lacking, etc.—in an ample-sized planting hole to give a plant a good start, and there is certainly a lot of merit in that.
I disagree because I have hostile soil: thick, red clay that is slimy in winter and hard as a rock in summer. If I fill a big planting hole with luscious soil and all the nutrients a plant could need, that plant's roots will stay in that nice friable soil rather than venture into the surrounding native soil. I would, in essence, be creating a potted plant in the ground.
If a plant is going to survive and thrive in my garden, it must get its roots into the native soil as soon as possible. So I dig a hole just a bit larger than the root ball, and I mix native soil with the planting mix and toss in a handful of lava rock, which helps create air spaces in dense, clay soil. Since much of my garden is on a hillside, I dig a bit of a well above the plant to encourage water to go down rather than run off. Next, I water the plant thoroughly and add a thick layer of mulch.
If you do subscribe to the "$50 hole for a $5 plant" theory, I suggest you at least mix a generous amount of your native soil with the new soil, so the transition to the native soil isn't such a shock.
Myth: Fall is the best time to go to the nursery to pick out plants to add to the garden and landscape.
Uprooted: While nurseries encourage you to plant in the fall, their inventory is not usually the best. They stock plants at their peak of perfection to entice you to buy while they are in bloom, or their fall color is at its best, or they are producing berries. It's hard to convince someone to buy a plant when it is dormant or not in flower. So yes, get ready to plant this season, but look all year long so you can go to the nursery with a list of what you want. Fall is the best time to plant, while temperatures are mild, rains are just beginning and plants can begin with solid root growth before the demands of spring arrive.
Myth: Drought-tolerant plants don't need any water during the summer.
Uprooted: False. Drought tolerant means a plant, once established, can survive periods of drought without dying. All plants need regular water to become established. It takes about two years to get perennials, shrubs and trees established. In addition, during a drought the plants may look terrible and near death. Parts of the plant may die, but once the drought is over, the plant will recover. Drought tolerant doesn't mean you can plant it and walk away or that it doesn't need and appreciate summer watering.
Myth: You should plant the biggest plant you can afford rather than wasting your time planting small ones.
Uprooted: False. Unless you are required to plant 5-gallon shrubs and trees or you need instant gratification because company is coming the next day, I'd suggest planting smaller plants. I've read again and again that by the time a large plant gets acclimated in the ground and begins to grow, the smaller ones planted at the same time have caught up with the big ones. Plants in 1-gallon containers are certainly cheaper than those in 3- or 5-gallon pots (they now call them number ones or fives because someone measured the pots and said they weren't really a gallon). Another advantage to buying 4-inch or 1-gallon-sized plants is ease of planting. My soil is hard and rocky, and I don't want to dig any bigger hole than necessary.
Myth: When trimming trees, you must cover newly pruned areas with a wound dressing.
Uprooted: False. Years ago, tree trimmers used an asphalt product that had the consistency and color of tar to cover newly pruned trees. This wound dressing was used only on larger branches. But researchers discovered the tar-like products trapped moisture under the wound and eventually led to disease and decay. If you look closely at the base of the branch, you'll see the bark tends to go around the branch rather that out toward the end. This area is called the branch collar, and if you trim just to the branch collar, the tree seals the wound. The result: no disease organisms getting in and no rot. If you don't like the raw look of large cuts on trees, you can use brown spray paint to hide the raw cut.
Myth: Always put gravel at the bottom of the pot for better drainage and to keep the soil from slipping out of the hole when watering.
Uprooted: You don't need to put anything over the drainage hole at the bottom of the pot for container plants. The myth is that the gravel will prevent rot at the bottom of the pot, but the exact opposite occurs: Instead of excess water draining out the hole, it puddles around the gravel so the plant roots are literally sitting in water. For great drainage, I use a coarse potting or planting mix, one with plenty of organic matter, in my pots.
Myth: All trees need to be staked when they are planted.
Uprooted: A tree does not need to be staked unless it cannot stand on its own, and even then, the staking should be temporary. Most people are guilty of three staking sins:
- Leaving the nursery stake tied against the tree trunk at planting time—A tree needs to be able to move to develop its "muscles" so it can withstand wind and driving rain without toppling. That nursery stake is used because potted trees are often pencil thin and have to be staked to stand up in their pots. Once planted, check the tree to see if it stands upright without support. If it stands without leaning, don't stake it.
- Staking the tree improperly—If the tree needs stakes, place two wooden stakes (never use fencing t-posts) 12 to 18 inches away from the root ball. Use strips of nylon pantyhose or gardening tape to tie the tree to the stakes. Loop the ties around the tree trunk and the stakes at the lowest possible spot that holds the tree upright. The tree should be able to bend and move, but not flop over. To find this point, start at the base of the tree and run your hand up the trunk. When you come to the spot where you can hold the tree straight, put the ties there. The stakes should be just a few inches taller than the spot where the ties are placed, and certainly not tall enough to interfere with the tree canopy.
- Leaving stakes on too long—Remove the stakes after a year unless the tree is still unable to support itself. Most people never remove the stakes, and an arborist I know said that's like wearing a cast all your life.
Proper planting, proper staking and proper care produce a tree with a strong trunk and root system that will be able to withstand most anything Mother Nature tosses its way. Look at how palm trees withstand hurricane-force winds: No one ever stakes a palm tree.