What Would Happen If…

March 21st, 2023

   One of the best ways to learn gardening is to try a few educated experiments and see what happens.

My gardens have served as test labs often over the years.

   You can’t beat it for first-hand feedback and for determining whether generally accepted advice is going to work in your yard or not.

   I’ve been doing that for more than 40 years now in three different yards. The results contribute a lot to how I garden, which, by the way, is still constantly changing as I find out new things and adjust to the ever-changing climate, environment, and animal situation around me.

   I thought I’d go over some of my past first-hand experiments in hopes that some of them might help you in your own garden… or inspire you to try your own experiments.

Do you have to start over with fresh potting mix every year in your containers?

   The word on potting mix is that you should empty and clean your pots each year before refilling them with fresh potting mix. The argument is that it prevents disease and heads off compaction as the medium breaks down.

   Potting mix got expensive enough that I experimented with salvaging about half of my existing mix each year and blending it with 25 percent fresh mix and 25 percent homemade compost from my bins.

   I haven’t run into disease or compaction issues, and my potted plants seem to do just as well in my “hybrid” blend as 100-percent fresh mix.

This is what wood-chip mulch looks like on a bed.

Can wood chips from ground-up trees be used as mulch?

   I gave this one a first-hand try when I moved and had several dead trees cut down. I wanted to recycle as much as possible, so I had the tree company leave the chipped branches on site.

   I saved a bundle of money on purchased mulch by moving scores of wheelbarrow chip loads to beds that hadn’t been mulched in 10 years.

   The chips looked a little “rougher” than the smooth brown carpet left behind by shredded hardwood mulch, but they did a good job holding down weeds, and they haven’t decayed as fast as shredded mulch (three years of coverage vs. one or two).

   I haven’t seen any detrimental plant effect, including the so-called “robbing of nitrogen” that fresh chips supposedly cause to the soil surface. Verdict: I’ll use whatever wood chips I can get my hands on.

Will moving a struggling plant kill it? Isn’t it better to just fertilize?

   I’ve found just the opposite here. Whenever I’ve encountered a plant that just isn’t doing well in a particular spot, I’ve found that digging it and either improving the soil or moving it to a more appropriate site almost always leads to a rebound.

   If a plant is going downhill due to a siting or planting deficit, and you just watch and do nothing, it’ll likely keep sliding into gradual death.

   Since lack of fertilizer is hardly ever a cause of plant death, fertilizing seldom makes a difference.

Tender plants can be stored over winter in a trench like this next to a heated house wall.

Can cuttings and other new plants be left outside in winter?

   Each year my wife and I take cuttings from many of our shrubs, mainly to give away as prizes on our garden trips.

   Growers also each year send me a selection of very young (usually first-year) trees, shrubs, evergreens, and perennials for trialing purposes.

   These young and tender plants often don’t fare well out in the open garden, so I usually keep them in their pots until their roots are more developed.

   On the other hand, many of them prefer to go dormant over winter and might not fare any better in the heat and dryness inside (not to mention the higher risk of bugs and the fact that I don’t have the space to grow all of them inside).

   My solution has been to dig trenches along the west-facing wall of my brick house and sink trays of the still-potted plants into them at ground level. Then I cover the ground with a couple of inches of fallen leaves.

   That protection is enough that almost all of my young plants survive winter without any damage. This technique has been a real winner.

Do you need to dip cuttings in a rooting hormone to get them to root?

   The advice on rooting new plants from cuttings usually says to dip the cut ends into a rooting powder before sticking them into a coarse potting medium.

   I’ve tried cuttings both with and without hormone powder and found that most plants that root well from cuttings do so whether you use the hormone or not.

   Maybe the powder gives you a slight boost in some cases, but I’ve skipped using it with good results.

Lots of tender plants survive surprisingly well in an unheated garage over winter.

Do you have to grow tropicals and other non-hardy plants under lights inside to keep them alive over winter?

   That’s definitely a “safe” way to keep your elephant ears, oleander, banana plants, Zone 7 salvias, papyrus, and other tender plants alive for another year.

   However, I’ve found that a lot of semi-tropicals and borderline-hardy plants will survive in a dormant to semi-dormant state if stored in an unheated garage over winter.

   I discovered that by accident one winter when I left a ‘Black and Blue’ salvia in a pot that I moved into the garage in the fall, then ignored it. When I went to replant the following May, I found the salvia was pushing new growth – even though temperatures had gone down into the teens and I hadn’t watered at all.

   Ever since, I’ve kept a lot of my tender plants in the pots all winter, giving them nothing more than an occasion light watering (enough to keep the roots from completely drying but not enough to trigger new growth).

   I’ve been amazed to see how many non-hardy bulbs, tropicals, and even annuals such as geraniums, lantana, and salvia come back. I look at anything that survives as a free bonus because they all would have died if left outside in winter.

Do homemade deer repellents work?

   Store-bought deer-repelling liquids are expensive, so I thought I’d try mixing my own, based on a formula developed by Brad Roeller, the former grounds manager at the Cary Institute of Ecosystem Studies in Millbrook, N.Y.

   The brew worked pretty well, but the caveat is that I had to keep applying it at least once a month. If I missed keeping the scent fresh enough, deer came back in.

   The formula is a half-cup of milk and one tablespoon each of cooking oil, dishwashing liquid, hot sauce, and oil of rosemary (the key ingredient), all mixed well in a gallon of water. (The recipe also calls for an egg, but that kept clogging my sprayer no matter how well I mixed and shook it.)

   Roeller recommends applying the spray every 10 days on above-40-degree days.

Does Irish Spring soap repel deer?

   I heard this one from more than one source, including a horticulturist who said the scent from that particular brand actually worked in his garden.

   I hung bars from several of my young trees, but deer browsed all of them anyway. The soap made no difference, other than maybe keeping the mulch cleaner underneath.

   At least I salvaged the bars to use in the shower.

This is a colony of nigella seedlings that came up from the prior’s years plant.

Can you replant plants and flowers that come up on their own?

   Weeds aren’t the only plants that pop up in spring. Sometimes flowers and vegetables that you grew last year dropped seed that comes up the following spring.

   The trick here is recognizing that these are seedlings from last year’s plants and not new weeds.

   Assuming you recognize the seedling as a tomato or a zinnia, you can let it grow or even transplant it to a new site.

   I’ve saved a lot of money on new annuals by simply watching for new impatiens, zinnias, marigolds, tomatoes, celosia, and melampodium to pop up, then moving them where I want them.

   The catch is that if you were growing hybrid varieties, the new seedlings might have some different traits than the ones you grew last year. You’ll get a tomato from a tomato seed, for example, but it may not be as big and tasty as the variety you grew last year.

   On the other hand, these are free plants. And anything new and suitable you get is a bargain. Anything that isn’t panning out well can be yanked.

Is a tree doomed if a rodent or other animal girdles the trunk?

   Well, it’s certainly not a good thing when an animal eats into the bark the whole way around a trunk. That definitely can kill a woody plant.

   However, I’ve salvaged several trees and evergreens by staking up a surviving branch still alive below the damage.

   Animal girdling might kill everything above the point of the girdling, but if the plant’s roots are fine, it’s possible it could send up new shoots or to continue to grow existing branches coming out below the injury.

   I once saved an apple tree by staking up a lower surviving branch, allowing it to become the new leader. I cut off all of the dead wood above it. After a year, I removed the staking, and the branch went on to grow new side shoots as it shot upward. Years later, you’d never know the tree suffered a near-fatal blow.

   I’ve used the technique successfully on several other trees and shrubs over the years. Moral: Don’t give up on those girdled trees. Stake and be patient. And wrap the new trunks so rodents don’t get that next.

Do CDs scare birds away from the blueberries?

   Anyone who’s tried to grow blueberries knows that the biggest challenge is keeping birds from eating the berries before you get them.

   I protected my seven bushes by draping them with netting for years. Then I read that if you hang CDs from a line over the bushes, the glare and movement of these shiny objects shush birds away.

   That didn’t happen at all. Birds ate every last berry, and I even saw some of them sitting happily on the poles I erected to hang the CD-laden lines.

   Total failure. I went back to netting.

This electric fence gizmo didn’t stop groundhogs in my garden.

Does a low electric fence keep groundhogs out of the vegetable garden?

   York County Master Gardeners told me they had been having great success using a single, ankle-high, electrified line to keep groundhogs out of their trial garden in Rudy Park.

   So I bought a battery-powered unit, strung line all around my vegetable garden, and turned it on.

   It seemed to work at first, although I tripped over the line a couple of times when I forgot it was there. Then one morning I found my beans devoured when the unit ran out of power and stopped working.

   However, groundhogs did more damage in the following weeks, even though the unit was working. (I took a few shocks myself to verify.) I think the lure of the veggies was enough that the groundhogs 1.) jumped the fence, 2.) timed entry between the unit’s pulsed shocks, or 3.) flat-out sacrificed a shock in exchange for a meal.