Hi, Rosie,

A moldboard plow can basically turn the soil upside down, burying any seeds that had fallen on the surface to an impossible depth (8 to 12 inches) to germinate from.

If you don't have access to a moldboard plow (like most people, I don't), you can till the soil. That will bury most, but not all, seeds sitting on the surface to an "impossible" depth. But It can also bring up some old weed seeds for a second chance. I have a tiller, a mid-tined Merry Tiller, and use it several times a year. I have a fairly large zinnia garden this year, as you can see from this picture, taken late last Spring.

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The "hoops" were supports for fabric-covered low tunnels, so that I could plant some zinnias before the last killing frost. I breed zinnias as a hobby, and I hope to have a larger zinnia garden next year. In this climate, volunteer zinnias aren't much of a problem, but I don't know whether cleome reseeding might be.

I would be leery of a "chemical" solution. There are chemicals that "sterilize" the soil, killing off all plant material until they, the chemicals, decompose. People who are starting a new lawn, or refurbishing an old lawn, sometimes use them. You might want to investigate that approach for your garden.

I am not an organic gardener, so I wouldn't rule out the soil sterilization treatment on that basis, but I would hesitate to sterilize the soil when the use of a simple garden hoe, or my tiller, might do as well.

ZM

You could put down mulch which would cover the seed. Shredded leaves work well.

I have not tried it but know that people put down Preen or other pre-emergent chemicals to prevent seeds germinating. That only works as long as the soil is not disturbed after putting it on. It forms a barrier that is broken if the soil is disturbed.

zenman, I can't till this area. It's full of many varieties of perennials, shrubs, smallish trees, many succulents and lots of different groundcovers.

What do YOU do to prevent seedlings (unwanted) from coming up? I hope I can solve the problem here of many hundreds of zinnias sprouting. Then I want to get your advice on types that will stay shorter than the 4'+ ones I have now.

Surely there's a solution. I just haven't figured it out!

Rosie

Hi, Rosie,

"What do YOU do to prevent seedlings (unwanted) from coming up?"

I don't do anything to keep unwanted zinnias from coming up, because they will be killed in a few weeks by a Killing Frost. I suppose that in your area a Killing Frost is not so dependable. And my situation is different from yours, because I can till my zinnia beds with my Merry Tiller.

Your situation eliminates the big guns: plowing, tilling, and soil sterilization. I think in your case I would cover the areas where you plan to plant your new low-growing zinnias with some heavy weight clear plastic. Solar heat will build up under the clear plastic and it will get so hot that any seeds in the upper inch or two of soil are killed. Then, when it comes time to plant your new low growing zinnias, you can remove the clear plastic and plant your seeds in weed-free soil. That includes the tall zinnia seedlings from this year's crop, which as "unwanted plants" qualify as weeds.

I understand your preference for shorter zinnias next year, rather than four-foot-plus zinnias. We had a high wind storm a couple of nights ago, and many of my tall zinnias are lying prone on the ground. A few even suffered broken stems. Some had been protected by zinnia cages (re-purposed tomato cages) and some had been tied to re-bar stakes, and they are in decent shape. But many are now going into contractor trash bags as part of my Fall cleanup.

" Then I want to get your advice on types that will stay shorter than the 4'+ ones I have now."

You have a lot of choices for zinnias that stay shorter than 4 feet. The big question is, how short do you want them to be? I used to like and grow really short zinnias, but now that I am a senior citizen I don't like to stoop, bend over, or kneel to work on my zinnias. (I am an amateur zinnia breeder, and I do a lot of hand pollination and cross-pollination of my zinnias.) So I prefer my zinnias to be in the 17-inch to 2-foot height range, such as the Whirligigs and Burpeeana Giants. My "toothy" strain is derived from Whirligigs.

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Some of my "toothies" show their Whirligig heritage with two-color petals, which are on rather low plants in the 17-inch range.

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However, many of my zinnias are still in the 4-foot to 6-foot range. So I stand up to cross-pollinate them. When I grow tall zinnias, I take my chances with our Kansas winds and brace some of my better specimens against storms by caging or staking them.

I get the impression that you don't mind if your zinnias are much shorter than I prefer. If you also don't mind if your zinnia blossoms aren't very big, then you might want to consider the Zinnia marylandicas: Profusions, Pinwheels, and Zaharas. Their flowers aren't very big, but they make nice beds and are resistant to Powdery Mildew.

If you prefer larger zinnia blossoms, you will need to stick with Zinnia violacea (elegans) for the time being. Their blooms can be much larger than the Marylandicas, but they are susceptible to Powdery Mildew, especially in cool, dry Fall weather.

So, which direction are you considering? The Marylandicas or the Violaceas?

ZM

It's my understanding that soil sterilization kills all the beneficials in the soil also, which I certainly don't want.

zm, I meant what do you do in the spring to prevent unwanted seedlings.

I don't know at this time which I'd want to grow in this big sloped bed. I'd like to open the view from the house to the back of my property. Also have zinnias growing (volunteering) in the beds on the three other sides. Have no really special ones yet and would love to. All the kids who visit always leave with flowers they've cut. That's so much fun!

mnwsgal, Preen might be just the thing. I mulch a lot - have to with our Georgia heat and sun. Plan to put a lot of big bags of coffee grounds on this area during the fall and winter. The organic materials get eaten up very fast.

Glad I have some time to figure all this out!

This particular garden looks like a huge bed of crayons with all the mixed colors of zinnias. I want to keep that look, just have it more manageable, without the zillion volunteers that appear throughout the season.

Thank y'all so much for helping me!

Rosie

Hi, Rosie,

"This particular garden looks like a huge bed of crayons with all the mixed colors of zinnias. I want to keep that look, just have it more manageable, without the zillion volunteers that appear throughout the season."

You are pretty far south, so your winters may not be very severe. Here, where we get all four seasons in full measure, the winters are severe enough to kill almost all of the zinnia seeds. This year I had just one volunteer zinnia that I kept, and maybe less than a dozen that got nipped off with a hoe because they were in the wrong spot (garden path).

But even if your winters are mild, I would anticipate that you will see far fewer volunteer zinnias next Spring than you have been seeing through the Summer this year. Wet soil is about the worst possible storage condition for zinnia seeds. Unless you already have prior experience indicating that the over-wintering volunteer zinnias can be a problem, they might not be.

The summers are quite different. I have even seen zinnia seedlings emerging from brown seedheads while the zinnia flower is still up on the plant. Incidentally, seed eating birds frequently develop a taste for zinnia seeds, and can greatly control the number of reseeded zinnias. I put little "hairnets" on my breeder zinnia heads to protect the seeds from the birds.

But you are right. You do have some time to figure this out.

ZM

I don't know how large your area is but hoeing would do it.

come on rosie..

if you are leaving a trail of seedlings as you remove the plant ..... then your base issue is that you harvested the plant too late ...

become a little more attuned to the ripening of the seeds.. AND GET THE PODS OUT OF THERE.. BEFORE!!!!!! .. THEY RIPEN ....

yes.. when you do it early.. you leave gaping holes in the bed.. so what.. its better than the bazillion spring seedlings ...

your other alternative.. is to get rid of the over aggressive reseeders ...

and finally.. heavy mulch to cover the seeds that have been accumulating ...

avoiding the issue is usually easier than fixing it ...

over the years.. i have left many a nice plant behind.. as they ended up causing more work than they were worth ... AND CLEOME WAS ONE OF THE FIRST ... really now.. smells like skunk when bruised... can be overly large.. and reseeding like a gang of rabbits on crack ...

JUST QUIT GROWING IT ...

and same for the zinnia ... i think zen just stroked out.. lol ...

if you must have them.. give them a restricted bed .... and do not let them escape.. and be a bit more proactive on deadheading ... before the seed matures ...

good luck

ken

Rosie, I'm inclined to suggest a combination of techniques to solve your problem.

Mulching, timely dead-heading, some hoe action. I'd suggest pre-emergent herbicides but not if you direct sow your new plant varieties.

Okay, guys, I have some answers to your posts. I can't deadhead in a timely way. I have many hundreds of zinnias blooming all the time. And have a big number of gold finches who feed on them, strewing the seed. AND they grow among a zillion other plants - perennials, shrubs and smallish trees. When they first come up, I can and do thin them to about 18" and within a few weeks, a whole bunch more have seeded. Hope I'm painting a word picture for all of you. I rogue out extras when there's still room to navigate around them.

Flora, instead of a hoe I do it manually.

The zinnias in particular have more determination to grow than anything I have. I use cypress mulch because it tends not to wash on the slope.

Measured this bed yesterday. It's over 2000'.

rhizo, if I find varieties I know I'll love, will do a pre-emergent and start the seeds elsewhere.

Oh my - what to do, what to do??

I can't deadhead in a timely way. I have many hundreds of zinnias blooming all the time. And have a big number of gold finches who feed on them, strewing the seed.

==>> neither could i ... but there is no reason to leave them ALL until late fall .. plant wise ...

so if you goal is bird feeding.. then you have achieved your goal..

and should not complain about seeds everywhere ... birds are pigs... they are not neat eaters...

but that still doesnt mean.. you couldnt start making the plot dwindle ... say ... remove a quarter in sept.. a quarter in october.. etc... reducing the potential.. while still feeding your friends ...

ID your goal.. and do the best you can.. but you cant complain when your bird feeding goal.. competes with your cleanliness goal ... [well.. we will listen to you complain.. but there isnt much we/you can do... ]

2000 feet.. crikey .... could you give us a picture... i bet its splendiferous ....

good luck rosie.... oink!!!!

ken

Hi again rosiew. I also weed manually but to do that you need to wait until the seedlings are large enough to handle. Just keeping the hoe moving regularly through the garden removes tiny seedlings almost before you even realise they are there. Hand weeding is called for in amongst close plantings but hoeing sorts out larger less cluttered areas. It really is quick and easy. The techniques are not mutually exclusive. (BTW I'm talking about a well sharpened Dutch hoe here)

flora, I'm going to take my hoe to neighbor this morning and get him to sharpen it. Thanks for the reminder.

Don't know what it is with me and hoes. I feel awkward using them. Will work on that!

Rosie

Hi, Rosie,

"Don't know what it is with me and hoes. I feel awkward using them. Will work on that! "

Please notice that Flora was referring to "a well sharpened Dutch hoe". A Dutch hoe is considerably different from your familiar garden variety hoe. The angle of the blade is completely different, and it sits flat on the soil, rather than cut into it, and you use a Dutch hoe by pushing it forward to skim off the little weed seedlings.

I have several hoes, but I don't have a Dutch hoe because most of the "true" Dutch hoes are designed to cut on the push-forward motion only. A more convenient design will skim off the seedlings in both a push and a pull motion. There are several different hoes that are designed that way. One such design uses a diamond shaped blade, with all four edges sharpened.

Wolf Garten (a German garden tool company) makes an interesting line of interchangeable handles and tool-heads, and one of their hoe heads works in a push-pull fashion. The Wolf Garten pendulum weeder also works in a push-pull fashion. You would need to purchase one of the Wolf Garten handles to use with it. Actually, that link doesn't show all of the Wolf Garten handles. I have a much shorter adjustable length handle that isn't listed there.

Considering all the different brands and sources, there are probably over a hundred different hoes you could choose from. One of the more interesting ones I have seen is the Royal Dutch Hoe from Sneeboer. I am wondering what you would sharpen that thing with. It does look like a Dutch Hoe that has a push-pull action. I bet it is expensive. I think all of the Sneeboer stuff is. But, like the lady used to say on the TV commercials for an expensive hair products line, "I am worth it." Or maybe it was "You are worth it."

ZM
(not associated with any product or vendor mentioned or linked)

This post was edited by zenman on Fri, Sep 27, 13 at 6:34

I'm in agreement that an old fashioned "push/pull " hoe is a very effective and efficient tool. Rosie, I don't mean to sound condescending AT ALL but has someone showed you how to hold/use a hoe? We aren't born with knowledge of the technique....we learn by observation or instruction.

With a little bit of practice, it's a smooth and easy movement. If you respond to instant gratification tasks, you'll like taking a hoe to your garden. Wear gloves.

Y'all are being so good, helping me through this. I truly truly appreciate it.

rhizo, you aren't that far away. Why don't you come tutor me. I'd love to have a knowledgeable gardener at my side. And don't worry about seeming condescending. You are not. I leave that to Ken Adrian. I think I just gave up on using a hoe. Bought one of those pendulum weeders years ago. Must look to see if I still have it.

I'm really good at one thing: can accurately push/pull with a 7" kitchen knife, destroying everything in my path.
If anything has seed heads, it goes into a bucket, the rest I leave to decay in place.

More later. I'll practice a bit. Spent garden time in the kitchen yesterday after discovering I had mice and/or rats. Ugh. Sealed entry points behind the stove and refrigerator with steel wool, copper flashing, aluminum tape. And have traps set in my oven. So disgusting.

Outta here, Rosie

I am a great fan of the Japanese hoe, its only fault is the short handle which brings you to your knees. I like the way you can get right up to a choice plant stem. For years I looked for a long handled one, bugging tool venders for not making one when ever they were at a garden show. Last year there was a Japanese company at a garden show, and I asked the usual question, his response was yes, "do you want a left or right hand model"? It has been wonderful! All the marking on it is in Japanese so I don't how to get another one. I use a dutch hoe for paths and other open spaces. Al

al, I googled Japanese hoe and found a lot of examples. What is yours like? Great that you can now get what you want. Interested also in the left hand model. Only left hand thing I have is my Felcos.

Rosie

Hi Rosie, I googled Japanese hoe to see what was listed and was surprised at all the tools they called Japanese Hoe. I am just preparing to leave town for a few days, but will take a picture of both my short and long hoe when I get back. The regular short handled Japanese Hoe is pictured at William Sonoma, being called Nejiri Weeder. Right handled model shown. Al

Oscillating hoe is gratifying to stand up and slice off the plants with a u_shaped blade...very easy back and forth motion.

Corn gluten meal will prevent seed germination. So they say. I've never tried it. Get it at feed stores like Agway.

Susan, thanks for the reminder about corn gluten meal. I'll do more reading on that. It's extremely critical that the application timing is perfect - don't know if I could do it right.

Rosie

Rosie, are you friends with the staff at your local Extension staff?

rhizo, no, I am not. Since I moved to Gwinnett County from Fulton County, I've just been flying by the seat of my pants, doing a lot of research, learning 'sun' gardening which I'm thrilled with. Also using Gardenweb as a valued resource.

Why do you ask?

I have good success combating reseeding/weed seedlings by laying down cardboard or newspaper and then adding a layer of mulch on top. If I do this in the fall, the cardboard is still pretty intact by spring and then I cut through it to plant. In GA, you might try this in very early spring though as the cardboard might deteriorate faster.

troveoftrilliums, this is a brilliant idea. Thank you. If anyone has tips on how to prevent the cardboard sliding on the slope, please tell me.

Thanks!

Rosie

Hi, Rosie,

" If anyone has tips on how to prevent the cardboard sliding on the slope, please tell me. "

The anchoring pins used to pin down landscaping fabric should also work on holding cardboard in place. They are sort of like giant staples that penetrate 6 inches into the soil.

We were talking about push-pull weeder hoes before. These look like a couple of interesting push-pull weeder hoes. Both are interesting looking, and the circular one looks unique.

ZM
(not associated with any product or vendor mentioned or linked)

I have a bit of a slope and found that wetting the cardboard/newspaper layers (several layers of newspaper was harder to put down initially but once wet, it stayed in place better) helped it contour to the soil and then not slide off. Wood chips tend to get washed away but the shredded mulch stays on better. Good luck!

Rosie, I asked about your local extension office because it may be a good source of information for you.

I thought of something else that may be helpful. Pine straw has proved to be more superior as a weed suppressant than bark or wood chips. This effect is both biochemical and physical, and has only been observed with the long needled varieties, such as Loblolly or Longleaf.

Pine straw is commomly harvested from the Loblolly pulpwood monocultures throughout the south. You should find it in bales or bulk all over the place in your locale.

Caveat emptor.....the big box stores can be terrible sources for fresh pine straw. Their bales are likely to be gray and dusty inside, poorly packed, and not worth the price.

Rhizo, you are so right about the straw. I seldom get it, but the differences in bale size, tightness, weight at a REAL nursery are significant. Landscape contractors aren't buying the junk from the big boxes - well, maybe some ignorant ones are.

I've been using cypress mulch on my slope, but will try a section with pine straw. Chose the cypress because it seems pretty stable on the slope, but neighbors have straw which doesn't seem to wash. Also, if it does wash down, it's a lot easier to put back in place.

Thanks for a very good idea.

Rosie