Meet the "Bubble SIP" a clay pot with no drain hole.
Bubble SIP - Sansevieria 'Hahnii' in a no-hole clay pot with SIP "bubble" inside. Stay tuned for more decorative bubble SIPs coming soon! Note that bubble SIPs are scalable. I will soon post a photo of a 7-gallon bubble SIP that is big enough to grow tomatoes.
The Sansevieria was growing in a recycled soda bottle SIP. These are the best planters for teaching kids (and their families) about plant science and horticulture. They are the cat's meow. I like the techie look but not everyone does. No problem. When you get tired of looking at it, simply move the plant into a no-hole decorative pot like this clay pot with "bubble SIP" plumbing. It doesn't get any simpler than this. Any no-hole decorative container becomes a water, time and plant saver. Look for more ideas in future posts. See more photos below.
This is about plugging unneeded drain holes in plant pots, in this case ubiquitous clay pots. They are wasting precious water all over the country...and the world.
For those who love the look of clay pots, that’s fine but they do not need to have any type of drain hole for indoor use. Drain hole pots waste water and provide no benefit in spite of what most houseplant and gardening books say.
The people who relentlessly write this drain hole stuff are living in a prior century horticulturally. Or, they may have a business plan they protect that does not include plant sustainability à la "Here today, gone tomorrow." "Aw, gee" they say, "It's only a little white lie."
The truth is that the benefits of sub-irrigated planters (SIPs) are many. Here are a few:
* SIPs save water in the range of 70-80% as compared to drench and drain watering.
* There is no messy run-off to damage furniture or floors.
* The "bubble" under the plant supplies water which is gradually used. The empty space in the bubble supplies vitally needed oxygen which is equally as important as water. These oxygen and water bubbles (aka reservoirs) are the primary reason plants maintained in SIPs are healthier and have long life spans.
* They save plant care time because of the built-in water reservoir. In addition, you can water plants on a fixed schedule, regardless of plant species or origin. Desert plants like Cactus and water-loving Peace Lilies are equally at home in SIPs. It's only a question of how much water you add to the "bubble" reservoir.
* With proper use, they prevent over watering and plant death. Over watering is a major cause of houseplant mortality.
Stay tuned for a post this coming week about water management in SIPs. It is based on what greenhouse growers do to manage proper soil moisture. It does not involve sticking your finger into the pot.
Note that sub-irrigated planters (SIPs) for outdoor use need an overflow drain hole in the side. I will cover the subject of positioning and drilling these holes in a future post.
The one and only need stated for drain holes is the big bad bugaboo about soluble salts. It is a myth unless you are using some very hard water from a well perhaps.
I have maintained the CuGreen indoor plant lab with city water for more than 15 years in San Diego and Brooklyn and have never experienced a soluble salts problem using sub-irrigation.
Back in the 1970's, I started using SIPs in my interior plantscaping business in Los Angeles and had no soluble salts probems there either.
The threat of soluble salts problems is based on greenhouse growing rather than home gardener usage. Greenhouse growers pour on the water and fertilizer (soluble salts) to push the plants out the greenhouse door as quickly as possible.
This is not the way home gardeners water and fertilize plants (particularly houseplants under low light). Houseplants require only a fraction of the water and fertilizer used to produce them, ergo minimal exposure to soluble salts.
As soon as you start growing in SIPs you will discover a miraculous new way to maintain plants in containers. Just remember that you cannot grow plants in the dark whatever watering method used.
The first step to get growing in SIPs is to plug the drain holes. A simple method is to put a piece of duct tape over the hole from the outside. Then fill the hole from the inside with silicone sealant.
I did not have silicone sealant at the time I plugged the hole in the pot shown. I glued a piece of thin plastic over the drain hole (cut from a food container). I used Goop clear glue, which I use for making all kinds of SIPs.
Clay pots are semi-porous so spray the inside of the pot with tree wound spray. Or, use spray paint (2-3 coats, as shown in the photo).
I made the water and oxygen “bubble” shown from the bottom of a yoghurt container. The bubble is approximately 3 ½” dia. x 1 ½“ h. This is a somewhat arbitrary size based on the pot size and experience with SIPs.
There are several ways to create the aeration holes. I use a metal skewer heated over the gas-stove burner. You could also use a cordless drill or Dremel to make 1/8” holes. Another way is to poke the holes with an awl. Note that this works with thin plastic, not thick.
The fill-tube is ¾” outside diameter, 5/8" inside diameter vinyl tubing. It is readily available in big box and hardware stores. Use a funnel to pour the water into the bubble.
I poke the small aeration holes with a hot metal skewer heated over a gas stove burner. You also need a 3/4" hole to insert the fill pipe. Rather than drilling in thin plastic, I heat a piece of 1/2" diameter pipe over a gas stove burner and melt the hole. Carefully move the hot pipe in a circular direction to enlarge the hole from 1/2" to 3/4" diameter. It is good to have a piece of the 3/4" tubing handy to check the fit. It's actually quite easy to do in thin plastic like this. It's a good idea to wear gloves while doing this to avoid a burn wound.
I do all this with the bubble installed inside the pot (see below) and spot glued with Goop for stability while creating the holes.
Pack some potting mix (peat or coir, shredded bark, perlite) around the bubble. Tamp it down to form a soil wick. The soil wick starts the water to move up by capillary action. Meanwhile the plant roots grow down to find the water. Plants may not have a brain but they are relentless in finding water. When you grow some indoor plants in recycled soda bottle SIPs you can actually see this happening. Very cool.