I have been told that roses do not like being planted in ceramic, clay or metal pots and that it is best to plant in plastic pots. Is this correct?
I first began planting roses in pots in the mid 1980s. I should add, all of my rose growing experience has been either in the inland valley heat of the Los Angeles area; coastal ācoolthā of the West Side and Pacific Palisades area āat the beachā around LA and now on the California Central Coast between Santa Barbara and San Luis Obispo. Ceramic and terra cotta ARE ācooking utensilsā. There are good reasons cooking pots are made from those materials. They heat quickly, transfer that heat to their interiors very efficiently and retain the heat for long periods. Plastic will heat as long as the sun shines directly on its surface, but once the sun moves off its surface, it begins releasing that heat and completely sheds it significantly faster than either terracotta or ceramic. The same goes for metal. Cooking pans and pots are made of metal for the same reasons. If you must use either of those three materials, you would do well to insulate their interiors with layers of styrofoam or many layers of large cell bubble wrap to prevent the rose roots from growing toward the warmth of the pot walls and circling them as they grow, exposing them to the greatest damage from extreme heat or extreme cold transferred from the exterior of the pot through the pot wall. In my experience, the best materials to use for pots in situations where there is going to be extremes in temperatures transferred into the root balls are concrete, foam or wood as all three have significantly greater insulation values than the ceramic, terracotta or metal. Foam and wood are lighter in weight like the plastic pots are while concrete provides the extra benefit of weight to help prevent winds from toppling the pot. But, concrete is expensive and that weight makes it a bear to move into position and probably completely unsuitable if youāre considering growing your potted roses on a balcony or roof top.
IF you are growing them potted in situations where the pots will be shielded from direct sun, ceramic or terracotta may suffice but any time the sun directly shines ON the pot surface, it WILL heat the roots and soil ball. If the conditions are hot and sun intense, it may be sufficient to damage or literally kill the roots. Whether it is or not, that extra heat will increase the amount and frequency of water you will need to apply and it will cause any time released fertilizers to break down and release their contents much faster which can cause salt damage if higher levels of the fertilizer have been applied. That extra heat and water will also cause your potting soil to digest and deteriorate faster as the bacterial action in the soil will be more active.
Of course you CAN use those materials, however to do it successfully, you need to be very mindful of their positioning and either insure you are using very large containers so the volume of soil helps insulate the plant roots; the interiors are sufficiently insulated to prevent extreme temperature transfer to the interior or the pots are completely shielded from sources of heat and cold. While you MAY succeed for a while, just as many succeed in pushing zones, Nature WILL catch up with you eventually. And she is unforgiving when she does.
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Many thanks for the detailed response to my query. This is much appreciated and has given me much food for thought. I trust that others will also benefit from your in-depth response.
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Youāre welcome. Thank you. I hope it helps. I continue growing roses in pots due to seismically engineered soil, physically compacted to near ābed rockā density which provides stability in case of earthquakes. It also nearly totally eliminates drainage (no air space in the soil) so all roots grow to the surface under the sod and planting holes fill up with water, rotting anything planted in them. The most successful are planted in 15 gallon nursery cans. The main issue is weight and bulk. Even in the milder, cooler climate here, compared to the old inland valley heat, potting soil digests in a few seasons and the plants require repotting. Hustling a 15 gallon root ball with the corresponding top growth can be a bit ācumbersomeā, particularly as the āmileageā racks up. Something to keep in mind. Good luck!
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Thank you. I have seriously enjoyed the science behind planting roses in pots. It is not quite as simple as what I thought it to be. I live in Lexington in Kentucky. The winters are severe and the weather quite varied. The locals (I originate from South Africa) say if you donāt like the weather wait 5 minutes and it will change. This is just what it is.
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Youāre welcome. Given that information, Iād consider foam pots. Theyāll insulate better due to the material. Theyāre lighter in weight, making moving them into garages for winter easier and repotting easier. Your choices of design and colors is fairly good these days so they can be prettier than the black plastic cans.
Many thanks once again. I seriously appreciate the time which have taken out to give me the advice which I was looking for. I will have a look around to see what I can get. Keep well!
Youāre welcome! Thank you, you, too!
Not really Ńause roses can grow perfectly fine in ceramic, clay or even metal pots as long as a few basics are right: good drainage, enough root space and decent soil.
Plastic pots are popular mostly because theyāre lighter, cheaper and hold moisture a bit longer. Clay and ceramic pots dry out faster, especially in hot weather, but they also breathe better and can help prevent soggy roots.
The main thing is pot size and drainage holes. Roses hate sitting in constantly wet soil much more than they care about the actual pot material.
Iāve actually seen some beautiful container roses thriving in large terracotta pots for years.
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Good morning Jonian, thank you for your input. This is much appreciated. Regards Conrad
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This is such valuable advice and honestly matches a lot of what Iāve seen with container plants in hot climates. People often focus on the top growth and forget how critical root temperature is. The comparison to cooking pots actually makes perfect sense - especially in areas with intense afternoon sun.
Iāve noticed black plastic containers can heat up surprisingly fast too, but like you said they cool down much quicker once shaded. Your point about roots circling near warm pot walls is really interesting and probably explains why some potted roses suddenly decline during heatwaves even when watered properly.
The insulation idea with foam or bubble wrap is clever, especially for decorative ceramic pots people already own. And I completely agree that bigger containers make a huge difference because the extra soil mass buffers temperature swings much better.
Really appreciate you sharing decades of firsthand experience instead of just theory. California heat is definitely a serious test for container roses!
Hereās my favorite variety (rosa rugosa) also, along with a great page describing how to care for them:
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Hi roseseek,
Much like you, I also grow my roses in 15 gallon nursery cans, although my reasons mostly involve furry little chew-devils ie gophers. I also live on bedrock, so thereās that. My question to you is: what do you use as your potting mix? And what does your feeding regime look like?
Thank you so much, your comments alone have taught me so much about growing roses.
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@Sheena_S thank you! Welcome back! Iām glad my experiences have helped you! I dealt with gophers and RABBITS for two decades back in the Los Angeles area so I do NOT envy your battles. I do wish you all successes with the fight!
Soil selection is rather climate specific. Iāve always grown roses in hot, arid conditions, so maintaining moisture levels in the pots has been a prime concern. I prefer Miracle Gro Moisture Control Potting soil, not the ālandfill contentā junk as it not only smells badly, but the roses go through a period of looking really horrid until whatever it is flushes through the soil or digests out. Plus, it seems to break down very quickly with heat and water. I like the āblue bagā stuff with COIR, ground coconut hulls as it supposedly retains a good deal more water than peat and prevents over watering by also maintaining a good level of soil oxygen and it seems to last longer than any others Iāve tried. HOWEVER, apparently, in wet climates, that product may remain far too wet and cause rotting, or so Iāve been told by several who have used it where rains occur regularly. If you actually receive rain (Iām on the Central California Coast, so ārainā can be sketchy some years) you may wish to consider something with less moisture retention.
As for fertilizing, all of my plants are in the back yard. I live in a āqueendomā Weāre a ābrood bitch, show dog retirement homeā as a many decades long friend of my spouseās breeds Toy Fox Terrors and places them with friends and grooming clients when she has a āgirlā to retire. They KNOW they are āroyaltyā and they ACT like it. The back yard is THEIR domain. They EAT EVERYTHING! Organic fertilizer? DOG FOOD. āPet safe snail baitā? DOG FOOD. Add, we have raccoons in the neighborhood and they haunt the yard every evening. āMischiefā is a climber. She LOVES the hibiscus sinensis blooms and the Santa Rosa plums and will literally CLIMB into them to help herself to a āsnackā. ANYTHING that contains any āanimal productsā is certain to attract the interest of one or both of the critters, so I am limited to water soluble fertilizers which donāt contain ANY pesticides nor fungicides. If something I apply in the yard makes one of them sick (or worse) it would surely kill me. The simplest and easiest fertilizer is Miracle Gro Liquid with its hose end applicator. I prefer the one with the four settings on the nozzle and green āwater bottleā refills out of speed and ease. We are required to use a hose end control with a shut off to conserve water. I like the MG applicator for that function, too, so itās what I use regularly to water everything. Is it āthe bestā? Most likely not. It does nothing for āsoil buildingā and it IS expensive compared to some types. I honestly donāt LIKE Scotts (manufacturer of MG products) but those products do what I need them to do where I need it done, so they are the ones I return to. The price is rather shocking. In the past decade, Iāve watched it explode from $10.47 a bag to $18.47 a bag., combined with a significant reduction in quality control. There is often a rather large variation from bag to bag. It used to be fairly easy to find it on sale for a flat $10 a bag but no more. We all know whatās happened to the price of fertilizer. I donāt feed the roses and other plants as often nor as heavily as you will read in ARS pages, so my costs arenāt AS extreme as they could be. I do recycle the coffee grounds every morning as āmulchā on whichever roses appear to require a shot of something new and they seem appreciative. I mainly feed anything which seems not to be performing as I expect it should be. I donāt cut flowers for the house nor do I exhibit. I grow what I enjoy and wish to use to breed seedlings which interest me, so my rose expectations may be different from many others. Iām probably a bit lazier than many due to āhigh mileageā, so thereās that, too.
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