"Busting" Common Garden Myths

National Garden Bureau
Can sugar in the planting hole
make tomatoes sweeter?

As diligent as you might be about heeding all the gardening tips you've heard over the years, are there some that you simply question their value? You wonder if maybe Grandma's advice really was the best? Or maybe has become outdated? We did! So, we turned to our members and asked for their professional expertise on a few commonly cited garden tips to find out if they were still applicable in today's gardening world.

So, here goes:

Myth: Pinch the seed pod off if the onion goes to seed.

Busted!: Years ago that was a common practice because older (heirloom) varieties were prone to bolting. In today's world with newer hybrids, if you pinch the seed pod off immediately it will keep the center core of the onion from growing and the end result is a smaller onion that will not store well.

Myth: Knock the tops of onions over to make larger bulbs.

Busted!: Actually the opposite is true. If you knock the tops over prematurely, that will stop the bulbing process and thus will make the onion more likely to grow during storage.

Myth: To get sweeter tomatoes, add sugar to the planting hole.

Busted!: Sorry Grandma, this is not true. Tomato plants can't absorb sugar in the soil, they produce it through photosynthesis. The sugar content of a variety is predetermined in the plant's genetics.

Myth: Perennials won't bloom the first year, especially bare-root.

Half Busted!: With modern breeding and growing techniques, this is no longer true. Go ahead and plant bare root and potted perennials now and enjoy those blooms the first year, assuming you don't plant them past the time they naturally would bloom. However, if you buy a potted perennial that requires over-wintering, then you will have to wait through the first winter to get the desired blooms. It's best to inquire from the seller to find out what to expect that first season after planting.

Myth: Plant peas and potatoes on St. Patrick's day.

Half Busted!: This can't possibly be true for all climate zones. It's much better to refer to the updated USDA hardiness zone map and plant according the local last-frost dates as recommended by local gardening experts. We assume grandma never moved far from where she was born so she must have lived her entire life in the same hardiness zone!

Myth: Pinch off all blooms of annuals before planting.

Busted!: In many cases pinching is no longer an absolute must because today's commonly available bedding plants are bred to be more compact with continuous blooms. So, you don't need the pinch to manage growth or promote another flush of blooms.

Myth: Planting tomatoes in a trench or up to the first true leaves promotes a sturdier plant.

Half-Busted!: This one is still true for seed propagated heirlooms and hybrids. Planting deeply does help elongate the rooting area since any point on the stem that comes into contact with the soil will root. The exception is when planting grafted tomatoes (plants and/or supplies for grafting are available by mail order) because if the scion takes root it will negate the benefits of the grafted rootstock so never plant a grafted tomato too deeply.

Myth: Use tuna fish cans around transplant stems to thwart cut worms.

Not Busted!: Yes, Grandma was correct and frugal with this tip! When both ends of the can are removed and placed around the plant, it acts as a barrier to keep these natural soil surface crawlers from reaching the plant until the stem has thickened past the tender stage.

Myth: Add chalk or egg shells to the planting hole.

Not Busted!: Again, a good tip, as both of these items will help prevent blossom end rot in tomatoes since they provide calcium to the fruit (since egg shells take a while to decompose, crush or grind the shells to enable them to dissolve faster).

Myth: Putting egg shell flakes around the base of plants will prevent slug damage.

Not Busted!: Yes, Grandma was right, slugs do not like to crawl over the jagged surface of sharp eggshells so putting a barrier of crushed (not ground too finely) egg shells is a great deterrent.

Myth: Beer traps for slugs?

Not Busted!: Yes, they really do work. And there is even research to show they prefer the light beers over the darker ales and lagers. But, if you get a rain or water the plants, you will need to refill the traps with fresh, undiluted beer as those little critters avoid the watered down stuff.

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