A few questions

[masscactus]

Hello All,

Some questions - I'd love to get some feedback:

1) M. sphaerica has finally produced many buds and will flower shortly (seems a bit late?). However it desperately needs repotting as it produced a LOT of new growth and is very crowded. As it is now August and I have been putting it off I really want to repot it so it has time to settle. What sort of impact will repotting have on flowering?

2) Has anyone noticed a difference in water up take when a systemic is applied to the roots?

3) I have a big? Theolocactus macdowelli purchased early this year at about 5-6 inch high and 13 inch or so around. It has produced 2 offsets. It is currently in a 5 inch standard pot. Would a 7 1/4 wide X 3 1/4 deep bowl be appropriate for this plant? I am unfamiliar with the root structure.

4) I have read many times the recommendation against gravel/rocks in the bottom of pots. I stopped this practice a while back and switched to a screening material. However I still have some pots with gravel bottoms. The plants within don't particularly need a repot yet so I haven't changed them. Is this an issue that warrants repotting in itself or is it ok to wait?

Thanks a lot! Any input/observation is greatly appreciated. =)

Bryan

[peterb]

Hi Bryan- M. sphaerica is pretty tough and I bet it would continue to flower even through a repotting process.

I've not noticed a reduction in water uptake after applying a systemic, but the last systemic I used was Orthene back in 1994, so don't know about imidacloprid or others.

The Thelo might want something a bit deeper than 3.25", or maybe not. You'll see what it might prefer when you unpot it, maybe have a couple options available?

Gravel in the bottom of pots causes no harm, IMO. I stopped doing it because it's not necessary, not to avoid harming the plants.

HTH,

peterb

[iann]

1. Sure go ahead. I like to wait for flowers to finish, but I haven't had any bad results from repotting plants with buds.

2. Not had a problem with Imidacloprid. Theoretically anything dissolved in your water could cause a reduction in water uptake through osmotic pressure, but cactus roots are pretty well adapted to suck hard.

3. You'll see the roots when you take it out of the pot. I don't decide what pot something is going in next until I see the roots. Unless maybe I've seen the roots before and know what to expect I predict you'll find a network of flexible fibrous roots that will work well in a shallow pot, although you might want to choose an even wider pot when you spread the roots.

4. Gravel in the bottom of the pot means you have a shallower pot than you might otherwise think, otherwise don't worry about it.

[TimN]

I agree with Peter, except on the pot. I think 3.25" will probably be fine. Plant it high in the pot with the bottom of the body just below the rim of the pot. When you get it out of the current pot, you'll know.

They sure are pokey when you try to repot them! The only advice I have is try to get someone else to pick it up for you!

Good luck!

Tim

[masscactus]

Thanks for the input everyone!

I started using Ortho systemic this spring, soaking the pots every six weeks or so. Last go round the pots dried normally etc. but the plants just didn't seem to respond the same. Just an observation.

As for T. macdowelli, ya, not looking forward to potting that one - it's a deceivingly hostile plant. Typically I pick the pot based on what I see when the plant is bare root. In this case it's a large(r) plant and I wondered if it, the species in general and at that size, had any known preferences i.e. wide shallow pots.

Bryan

[iann]

I'm not sure that soaking your pots in Ortho every six weeks is a good idea. A single systemic insecticide treatment to the plant should last for at least six weeks, and one applied to the soil should last many months. You are over-dosing and you might be seeing problems from this. I don't have Ortho, but likely symptoms would be phytotoxicity, scorching, and burnt roots.

[masscactus]

Thanks Ian.

I used about 2 TBS per gallon, under the recommended dose, this is only the second application. First application was in early June. I have been applying the second treatment as plants needed water this past 2 weeks so its been a bit longer then 6 weeks actually. I did not spray the plants and opted for watering, direct to soil, as normal with systemic included. Sorry if "soaking" was misleading.

Scrutiny has been high as I really worried about negative impacts to the plants. I haven't noticed anything unusual outside of the seemingly slow uptake for some plants in the last application. I dont see any evidence of scorching etc. but "root burn" sounds awful and has me worried...symptoms? What to look for? (I would imagine plants slow to uptake water...) Plants I have re-potted this year that had the first application have all had for the most part, excellent root structures.

In applying systemic I thought there are 2 ways to attack - either spraying the plant directly or applying to roots for uptake? As I am looking to prevent long term rather than combat an immediate outbreak, I thought the watering approach better for my goal. As for frequency - once a season is plenty? I had thought once in the start of the season and then roughly six weeks later would be good and then any additional based on results.

Ugh - the FUD factor has been incremented a few ticks. I am envisioning my plants at home sizzling away...

http://www.scotts.com/smg/catalog/produ ... d=cat50008

Bryan

[masscactus]

Hey all - can anyone provide anything additional here? I am a bit worried! Sorry for the long winded explanations, just looking to provide detail for accurate assessment.

What to watch for - symptoms of root burn? Some of the plants I dosed have been repotted since, and a few have had second waterings.

Every six weeks or so is too much? Even using less than recommended? Reading seems to say repeatedly that it takes some time for the plant to "build up" resistance.

Thanks - much appreciated.

Bryan

[peterb]

Hi Bryan- I'm not by any means expert in pesticide application, but I'm under the impression that systemics only work by being taken up into the plant tissues, so soaking into the soil is the way to go.

I'd imagine your plants are fine. This is a good time of year to flush the soil anyway, so I'd recommend letting them dry out until almost completely dry (a bit of voodoo there!) and then give them a deep clean water soaking two or three days in a row when the weather is hot, sunny and dry. (More voodoo!)

peterb

[daiv]

Bryan,
With only two watered down applications, I certainly wouldn't worry. I've been successful with a once per year application of systemic. Perhaps twice a year would be fine. But unless you are really having problems, that should be plenty. But again, I wouldn't worry based on what you've shared.

Daiv

[masscactus]

Thanks Peter and Daiv! Coming in off the ledge now.

[iann]

Tests with Acephate, the active ingredient in Ortho, show that it is translated to all parts of the plant in about 24 hours when applied as a soil drench, then it is metabolised into a chemical which is the actual insecticide. The Acephate itself is not especially toxic to insects, but the Methamidophos it is converted to is extremely toxic. Interestingly, when applied as a foliar spray, the Acephate is not translated throughout the plant, but is metabolised within the leaves, and then the Methamidophos is translated throughout the plant in about 72 hours. These tests were not on succulents, takeup may be slower if the plant is not taking in water because it is dormant or just not thirsty.

The product you linked to is not labelled for use as a soil drench so it is hard to tell whether you are using too much or too little. Standard use as a soil drench would be to saturate the soil at approximately the same dilution as a spray. Using at a lower dilution than directed is just a recipe for developing resistance in the insects, you should apply sufficient to kill pests not just give them a headache

Two applications shouldn't cause serious problems. Maybe you plants are not taking up water for some other reason. Maybe it is just your imagination. Maybe the weather is not so hot, or maybe it is too hot. Remember that the majority of water applied to succulents evaporates. If the problem persists to the point of the plants looking dehydrated even though they have been watered, that would be the time to worry, but not now.

[masscactus]

Thanks Ian.

The product you linked to is not labelled for use as a soil drench so it is hard to tell whether you are using too much or too little. Standard use as a soil drench would be to saturate the soil at approximately the same dilution as a spray. Using at a lower dilution than directed is just a recipe for developing resistance in the insects, you should apply sufficient to kill pests not just give them a headache

I had determined through reading here and elsewhere that this product was OK to use as a "drench". Perhaps that is an incorrect conclusion. As this is the first time I have used such a product, and was uncertain the effect it would have on my plants I opted for a lower dosage, which also seemed to echo others comments and reasoning.

Also I had thought that as I was not fighting an active infestation but looking to implement some pro-active protection, there was no reason to go "fully loaded" so to speak. Understanding that bugs gain resistance over time with exposure, my long term plan was to alternate products.

Definitely a learning experience. Thanks for the attention.

Bryan

[peterb]

I'm not sure, because I don't use pesticides (knock on a whole bunch of cholla wood), but I don't think they work in proportion to the intended job. I mean, if you have 20 mealies instead of 2000, using a dilute solution is probably not effective. Using systemics for preventive pest control probably requires using the full strength applied in the manner and at the time intervals indicated by the label, too.

peterb

[masscactus]

Thanks Peter, your point is understood.

After last years run in with mealies I was eager to begin some sort of program to prevent infestations of any sort and it seemed simple enough. Apparently my cautious approach leaves some gaps. This discussion obviously has me rethinking my strategy and reviewing sources.

A valuable learning experience, thanks again! I hope this thread help others as well.

Bryan