This has come up on many other forums. The idea of putting pebbles, broken crockery, et cetera is usually done by folks attempting to create a "drainage layer". Unfortunately, it doesn't work out that way. Instead, the result is a "perched water table" which can actually be detrimental to the plant's health. Al (talpa) has written a number of interesting (to me at any rate) posts on the subject. The following is an excerpt from one of his posts:

"If we use a “drainage layer” of stones/ gravel/ packing peanuts …, it doesn’t increase drainage. E.g., if we have a pot that is 12” deep and a soil that supports 6” of perched water at the bottom of the pot, adding a “drainage layer” simply causes water to perch to a ht of 6” above the drainage layer. Whereas the max height of the drainage layer would be 6” from the container’s bottom w/o a drainage layer, adding a 3” “drainage layer”would cause water to perch above that to a ht of 9”, which is actually an effort that ends up being self-defeating."

If interested, Yolanda, you can do a search for "perched water table" on the GW forums. You'll get a LOT of posts. I'd say look first for ones originally posted by talpa.

Irina, how much perlite would you use?

Yolanda

Half inch .

I looked at the perched water table info Paul provided - and I a lot of doubts regarding the info from the gentleman Paul quotes. The height of a saturated soil layer depends on a total porosity - the amount of small pores in a soil - adding loose gravel or perlite -with air filled pockets between rocks will effectively reduce the average total porosity of a stack of gravel with soil on the top - and decrease the thickness of a saturated layer.

That's why we add so much perlite to a soil - to reduce TP. The Optimara soil - we all deal with when we buy AVs in a big box store - stashes a lot of water - because it is mostly peat with plenty of pores - and it has a large water capacity - if you stick this pot in water - the whole rootball becomes oversaturated. So - if we want to keep this plant out of trouble before we repot it - we never give it as much water as it can absorb. With water standing in a saucer...the whole pot will become an oversaturated layer with not enough air pockets and roots will choke.

The oversaturated layer starts at the bottom water level - not at the level of gravel. That's why we use Oyama pots - and fill the submersed part of the inner pot with perlite. If we fill it with soil - our Oyama pot will be not working that well - we will have an oversaturated soil.

I.

IL and All, I do not wick water. I water about twice a week - Wednesday and Saturday. The amount of water I give IS NOT absorbed by the top layer of soil. The AVs flower, so they must be happy with what I do. I know when I first grew AVs a long time ago before the boyfriend and then husband and children, I overwater my AVs. I learned from that.

I add perlite to the soil for the drainage. Am I doing something wrong with the gravel at the bottom of the pot? I know some people use coffee filters. Should I switch to coffee filters?

Yolanda

Yolanda, I think the coffee filters at the bottom of a pot are purely to keep small bits of soil inside the pot when the drainage holes are quite large. Other people will use a small section of paper toweling for the same purpose. I have never had a problem with my potting soil escaping from the small holes I punch in K-cups or Solo cups, nor from the holes in the 3 and 4" plastic pots I buy. Seems like something unnecessary to me.

As to the gravel at the bottom, back when I would add water to the AV's saucer and let it pull up what it needed then empty any extra, I DID put a layer of coarse perlite in the pot and I think it saved me from overwatering if I occasionally forgot to empty the extra water in a timely manner. That was back when I only had a few plants to deal with. I wouldn't bother with that either with AV's now that I wick water and they are all on reservoirs in a very light soil with a lot of added perlite. It works for me, anyway.

My streps, however, are still bottom watered in a saucer and they get a 1" layer of coarse perlite in the bottom of the pot which I have found valuable in preventing root rot. If I skip that perlite layer on a strep when I'm repotting (ran out of coarse perlite one time and that is how I know) then I end up losing that strep in no time.

Yolanda!!!!! Good to hear from you again!!!! It has been a while!!!!

Ha ha!!! AnneCecilia is talking about me!!!!! I do use a small piece of napkin or coffee filter just large enough to cover the hole. I don't use an additional layer of straight perlite in the bottom of the pot. I wick water. I string the wick up the hole first then I put in my little piece of napkin, situate the wick and finish potting. Works well so far for me. Oh and my mix is about three quarters perlite to one quarter MG soil.

Even in pots I don't wick, succulents, floor plants and anything non violet/gesneriad, I always put a single layer of napkin/coffee filter over the holes. Since there are no roots yet to hold the new soil in, I don't want the soil to "fall out" ! Just my way, I guess.

When grandma taught me back in the day however, she always used broken pieces of terra cotta pots to strategically cover the holes so the dirt (and yes it was dirt and it came out of the garden!) wouldn't fall out. Then she added a few more pieces just for good measure so I guess all total she covered the whole bottom of the pot.

I just refined her method down to a small piece of absorbent but fast draining little piece of napkin/coffee filter. Works for me. I have tried to not use anything in the bottom of the pot and the water somehow gets dirty. So I use napkin/coffee filters. That's my story and I am sticking to it!!!!! (Today is a happy day!!!!!) Rosie

Rosie, I know it has been a while since anyone heard from me. I have a story. Our older daughter had a daughter on January 20, 2019. Her name is Aria Lee Justina Campbell. Since it was the first baby, I went to Kenora, Ontario, for about a week. I met the father's sister, her family and his parents, which was nice. We live in Toronto, which is a two-day drive. Kenora is north of Minnesota, on the shores of the Lake of the Woods, a part of which is in the States. I fell and broke my right femur. There was a half-hip replacement and an airplane trip home across the province/state. That is the story.

The important part is the AVs, which my husband watered. They seem to be doing well now that there is more sunlight. Some of my babies are flowering profusely in their Jello pudding cups. Recycling works with AVs. What can I say.

My AVs grow on window sills and are NOT wicked. I know people do not think there is enough room for furniture and people in a house with 1100 square feet. Homes here usually have a basement, which is not counted as floor space. There is about 1100 square feet in the basement for AVs, furnace, laundry room, sewing room and an extra TV room. There is enough space. We have lived here since 1981, and raised two daughters,

Thanks for your advice Rosie. I think your grandmother had her methods which worked for her and her AVs. I am trying to decide if I should change my potting methods. Some use some screening material. Some think my pebbles, which I buy at the dollar store, are strange. I do not know if there is something better. Maybe I should try the coffee filters acquired at the dollar store. For now, the old method works, but I will try the coffee filters.

Thanks, Rose.

Yolanda

OMG Yolanda! Nice story for the first part,,,,OUCH on the second part. But congratulations on your new granddaughter!!!! I have 2 grandsons, age 24 and 30. And 2 daughters. Love them all!!!

Boy,,,thank that husband of yours for coming through for the "babies" he cared for. For me, the only reason I wick is I was going nuts with constant watering. I had to give me a break. Wicking gives me a break. I don't have to fill reservoirs as frequently as I had to water. I was doing that continuously and it became far too much. So for me wicking is a great method.

Another reason I like the piece of napkin or coffee filter (used of course) is it doesn't have the weight of stones or rocks. Perlite doesn't weigh much either but I still prefer a covering of napkin or used coffee filter over the hole to keep the soil in. Just my preference. And it does work well for me.

HAHA!!!! I believe strongly in recycle! I use pudding cup, yogurt, condiment cups with lids etc., for my plants,,,,,and again,,,,,it works well for me! If I don't have to buy traditional pots,,,that is more money saved for violets! Right??? Right!!!!!

My violets are also grown on windowsil light. No room for a 3 tier shelf/lights proper. That is still the stuff I can only wish about. But that is ok.

On a last note, if your method works for you and you are content with it, by all means keep doing it. But keep it in the back of your mind just in case something starts NOT working for you and you need a different plan. Good to see you post again! Rosie

Rosie, I will keep the coffee filter/paper towel in mind. All of mine are grown on windowsills. Electrical power is expensive here, and I do not think my husband would like the added expense of additional lights on, especially when it gets dark earlier in the winter.

But , as always, it is what it is and no one can change it.

Yolanda

So right you are. I understand about electricity.

But here is one more thing, and this is just my logic,,,,, when you use pieces of terra cotta pots, marbles, perlite, small stones or anything else like that to plug up holes in pots, they are there forever. Until you repot.

However, napkins, newspaper (not glossy newspaper), paper towel, coffee filter or other paper products remember, as your pot fills with roots and grows it will also "use up" that paper product as its roots take over possession of the pot!!!!! Usually by the time I need to repot, there is no evidence of the little piece of paper product I used! Rosie

Rosie, what would be the difference if I used perlite. It would be at the bottom of the pot. Do you think the plant would "use" the perlite? Just asking.

Yolanda

hmm.........my only goal for a little piece of paper is to cover the hole to keep soil in. If I were to use a layer of perlite in the bottom, I would still use the little piece of paper and feel as though I was wasting perlite. Unless I was sure that a large piece of perlite sat squarely on the hole. I don't know. Why don't you try one of each and see what serves you well? I think water would still flow thru the hole if I used perlite. To me the paper square works best for me.

Just a question. I don't understand what good a layer of perlite (about 3/8 of an inch?) would accomplish unless you were keeping the water level higher and you wick water? I am not sure I am understanding a layer of perlite if you are not wicking.

I am not sure I am very helpful. I don't know what the difference would be or what you would have to change. The roots would eventually grow down into the perlite layer but no harm there I guess! lol Rosie

OK, Rosie: you know that I use that layer of very coarse perlite at the bottom of my streps' pots. They are not wick watered; I bottom water directly into their saucers and let them suck up the water. Streps especially don't like wet feet. The perlite layer (or a layer of gravel or rocks) gives a porous layer (think of the air in the spaces between perlite chunks) which acts as insurance against the soil at the bottom being saturated with water. Go back up and re-read what Irina says. It has nothing to do with keeping the soil inside the pot - it's all about letting some air get to the roots. When I grew my AV's back in the days when I only had 20 or so, I was using the perlite in the bottoms there, too because I had each plant in an individual saucer and bottom watered. I read early on that it would help prevent root rot and so it does, IME. Works for me. Now that I wick water my AV's on egg crate over trays, those AV's are potted in soil heavily mixed with perlite. With my mason's string wicks, I don't need the porous layer at the bottom anymore - I've worked out how light the soil needs to be overall for the wick to work properly - just wet, not soaked. And I don't put anything in the bottom of the pot before I put in the wick and potting mix - I don't really have any issue with the soil falling out even with those wide pots I use for the trailers with their multiple pre-punched holes that are 1/4" in diameter. If your soil mix is damp, it will not run right through.

And yes, the roots can and often do grow right into the perlite layer. No harm at all.

Thanks, Everyone, for the advice. I just planted up some babies that were in cups from Jello pudding cups. They are now in 3 to 3.6 inch pots, and they will be going to the rummage sale in April. I am not going to be showing them, nor do I plan to sell them on my own. At least someone else will enjoy them and they will NOT be in my house. I will have more room for new plants.

I still used the pebbles in the bottom of the pots. If whoever buys them, does not like that, they can change it. For now, even if others in the AV club think it is strange, it seems to work for me. I will have to try putting a coffee filter or paper towel in the bottom of the flower pot. There is the old saying, if it is not broken, why fix it. But new methods are worth experimenting with.

Just saying.

Let me know if there is any further advice. It is always good to share experiences with others who grow AVs.

Yolanda

Yep Anne,,,,I remember. But I completely forgot about your streps and the layer of perlite in them. I was focused on violets only. AND the only reason for my little piece of paper is so soil won't leak out. Maybe I have to come up with the times and do things the more modern way. You know me,,,,I tend to stick in the past! And maybe I will have to amend how I raise streps if I ever get one that far! Mea Culpa!

But different points of view give everyone new information! Never know what you may learn and find interesting!!!!! Rosie

1. Anne C. knows what she is doing

2, Toronto has some of the best AV growers in North America - and local advice is the most valuable you can get.

3. You never know until you try what works the best for your home. So - one pot with coffee fliter, one with perlite, one with broken pot shards.. In 2-3 months - you will decide what is the best.

;-))

Great advice Irina! Yes,,,AnneC. does now what she is doing! Rosie

Thank you both for that vote of confidence, but a few of my plants might disagree with you. Ha!

And sometimes I think that after all the research and the experimentation, success still comes down to a hefty dose of luck.

Not all plants grow for everybody. Some things just die on you no matter what. Accept it. And after 3 times - put them on a black list and save yourself the aggravation. Your conditions just do not match the natural habitat...

Luck comes with time and trial...when they start talking to you - you are in luck. Family members probably will disagree.. .8-((

Irina you have such the sense of humor! I do agree about the hefty dose of luck AnneC! Rosie

Hi All, thanks for all the advice. I will try coffee filters probably from the dollar store. I would hate to buy really good ones at a real expensive price to bury them in a flower pot.

Irina, you are right, there are a lot of good AV growers in and around Toronto. The club in Oakville, however, has disbanded. We have John Brownlie and his wife, Doris, who are members of the Lakeshore African Violet Club. They are both a good source of information.

Thanks to all.

Yolanda

Yolanda don't buy coffee filters, I use ones that are already used. I would be happy to put some in an envelope for you to experiment with. Private message me with your address and I will mail them out.

Also if you know someone who has a coffee maker get a couple used ones from them. I don't use new ones.

If you know someone with a Keurig coffee maker as them to save a couple used cups for you. Throw the grounds in the grass/flower bed etc and there will be a small paper filter inside of it that you pull out. Use that! And use the empty kcup to start a leaf in! Rosie

Rosie, I will try to get some coffee filters from my girlfriend. We usually drink instant coffee unless we have someone over. Hopefully, my niece will come for Easter dinner. Her father and mother, my sister, will probably still be in Georgian, where it is warmer, although by April, it will be warmer even here.

Toronto may be more progressive. Coffee grounds go into the recycling bin which gets taken away every week. The garbage and paper, etc. recycling gets taken away every second week.

I will private message you with my address. Just remind me how to do it.

Just saying.

Yolanda

Well, it used to be easy,,,,hover on my name and a box will appear. Click follow. I am already following you. Then see if you can go to your profile page and send me a PM. Anyone got any help??? Rosie

Used dryer sheets. I fold them in two to prevent some of the vigorous gesneriads from sendng theirlarge roots into my mats.

Oh my I completely forgot all about used dryer sheets!!! Perfect!!!!! Thanks Irina!!! Rosie

Recycle!!! But I draw the line - I do not launder my wicks.!

Well,,,,,,,the thing is,,,,,,well sometimes if you put them all in a baggie with a soapy, clorox mix and rinse very well they are good again!!!! It has been known to happen,,,,,,lol Rosie

I use mason twine... and it gets irreversibly salted with time...

WAIT!!!! Irina, I must admit,,,,I never thought of the wicks getting saturated with salts. duh! I understand the pots etc, but the wicks? Never thought of that,,,,thanks! Will no longer use old wicks! (enlightened) Rosie

I use mason twine #18 in combination with mats. It is pretty skinny = and will not work well without mats - it will easily dry and become bluish green, stiff and pickled.... I do not use yarn except for big pots.

Thing is - you twick it to your style... I normally put an half inch of perlite on the bottom to prevent the pots to become soggy. And I was getting ready for sale - so I repotted several - and didn't use perlite - general public will put them on the saucers anyway. Blizzard happened - and I didn't sell them. The ones tha I repotted - were getting to wet - and I lost one to rot. SO ...I knocked them out of pots, added perlite, put them back. Now - they are OK. For my soil, my mats and my wicks... I need perlite... People who keep them on reservoirs or eggcrate - probably can do without it.

Overly enlightened... I.

Thanks Irina! No such thing as too much "enlightenment"!!!!! Rosie

I heard that if you know too much... they will shoot you...

hmmmm,,,,,well I guess I will live a loooooonnnnnggggg time!!! lol Rosie