It really depends on the plant. You don't want to wanter all plants until the water comes out the tray. I'm sure the person was talking specifically about one plant.
I don't water my succulents near enough to see water later, ya know?

Hi Guest...Never give sips..water sparingly means, water until it escapes from drainage holes, then wait until soil dries before adding more.
Guest, no one can give a specific time to water. Test soil by the finger test, lifting pot for weight, or water guages.
Watering the right time depends on temperature, humidity or lack of, soil, pot size, etc. The cooler the room, the longer soil takes to dry, and visa versa.

I let most plants dry between watering, some more than others..during winter, when there are weeks of cloudy days, and because two rooms are kept cool, plants get less water. On the other hand, in summer, sun heats rooms up a lot, so, soil dries faster, which means, plants are watered more than they were during winter.
I don't mean quantity of water..'per drink'..Despite the season, the amount of water is the same..the difference is the number of times a plant is given a drink. Toni

For almost all of my plants (African violets being the only exception I can think of off the top of my head), I always water heavily, until water runs freely out the bottom of the pot, whenever I water. This is the same regardless of the plant and regardless of the time of year. I do water much less frequently in winter for plants that have a pronounced dormancy (Clivia miniata) or plants that are just obviously staying wet longer: I don't make the plant take the water if it's telling me it isn't using it.

Watering instructions (as well as instructions for light levels) are difficult to give, just in general. I do most of my decision-making about watering by the weight of the pot, because between work and home, I spend, no kidding, probably about 30 hours a week just moving plants from one location to another. Besides building biceps, this also gives one a real keen understanding of how much a pot of any given size weighs when it's wet, dry, and all stages in between. It's also completely useless when it comes to talking to customers, because normal people don't spend 15% of their life lifting plants. So I have to try to explain in terms of how far into the soil you should be able to stick your finger before hitting something damp, and I know I get misunderstood sometimes.

I would interpret "water sparingly" to mean, let the plant get very close to completely dry before watering it again, approximately like the watering for a jade plant or Dracaena. But to some extent, you have to learn through trial and error the same as everybody else, too.

* Watering technique is very under-rated in container culture and can easily make the difference between success and failure. To illustrate: When an apprentice goes to Japan to study under a bonsai master, he will often spend 6 months or more doing nothing but learning how to water, before he is entrusted with any work on the master's plants.

Ask a greenhouse plantsman what he feels is the most important job in the successful rearing of a crop, and his answer will be "proper watering" or "irrigation management".

* A generalization - With everything else equal, the more often your planting needs water, the healthier the roots will be, as long as you don't forget to water. The need to irrigate frequently indicates good aeration and drainage, which insures that air is returning to the soil before anaerobic conditions create conditions that cause the death of fine rootage or impair root function/metabolism. Watering also forces old, CO2-rich air from the soil and pulls O2 rich air in behind it.

* Don't water on a schedule. Water when the rootzone is first dry to the touch. This can mean watering new plantings (shallow roots) when the lower parts of the container are still wet, but for most established plantings, water when the soil at the drain hole first feels dry - or use the sharpened dowel trick. Push the dowel deep into the pot - if it comes out damp, you probably don't need to water.

Your sense of touch registers 'dry soil' when soils are still about 40% saturated. Plants, however, can still extract water from conifer bark and peat down to about 30% saturation - after that, water is held too tightly for plants to access. This gives you approximately a 15% margin of error in which plants can still extract water from soils, even after the soil feels dry.

* Your soil should at least allow you to water at every watering so that water drains freely from the drain hole. The best way to water a container is: Wet the soil until you 'feel' the container is about to start draining from the bottom and stop. Wait 10 minutes and add additional water until about 10-15% of the total volume of water applied in both applications exits the drain hole. The first water allows precipitate solids ( accumulated salts) to dissolve into the soil solution, and the second watering flushes them from the soil.

* If you cannot water copiously w/o risking root rot, you might want to consider a different soil with better aeration/drainage and durability. You may be able to partially correct soils that drain poorly by adding a wick through the drain hole of the container to remove excess water from the layer of saturated soil at the container bottom until the planting is mature enough to do it quickly enough on its own.

More drainage tips: Nesting the pot inside another pot with the same soil in the bottom of the second pot can remove all the excess water in a pot. Water moves downward into the soil in the lower pot (it "thinks" the pot is deeper & moves to the "bottom"), leaving the primary container free of saturation and improving aeration in the main pot immediately after watering.

Tilting the container after watering also causes additional water to drain. To confirm, water thoroughly & wait for the container to stop draining. Tip container at a 45* angle & you'll notice substantial additional drainage.

Also, if you hold the container at chest level and lower it at medium speed to waist level, then lift the container quickly back to chest height, you can use the physics of inertia of motion to help drain the container, too. Repeat until no additional water drains.

It is very important to return the entire soil mass soil to a well aerated state as quickly as possible after watering. It can make a huge difference in sustaining o/a energy levels and maintaining plants at maximum vitality within the limiting parameters of all the other cultural conditions plants must deal with.

Al

Out of curiosity then, Al, what would you recommend for plants like lithops? I have seen culture sheets that recommend watering with an eyedropper.

As to your "pot within a pot" method:

1) What would happen if you didn't use the same soil? For example, if the soil of the outer pot was less coarse than that of the inner pot? Would the inner pot soil become drier faster?

2) Would the pots have to be terra cotta? Plastic? Anything?

3) For those plants which truly require dry conditions (like lithops) any danger of too much water being wicked back up into the inner pot?

Lithops come from South Africa where very little rain is. Watering a lithops at any time other than active growth, (winter) will be the death of it.

Double potting is used frequiently in florist arangements, however for them to work as designed, the soil has to be about the same consistancy or the outer soil needs to be more porous. Clay inner pots also work better. I have used this method for my Schlumbergeras, with great success. I have used pure perlite, and aquarium gravel in the outer pot, both work fine.

Even lithops will eventually suffer from or succumb to increasing salt levels in the soil if you water in tiny sips. You may have to develop a strategy for watering plants that are very seasonal in their water needs, but you still need to have a soil that 'allows' you to water in that manner. IOW, you wouldn't ever want to grow lithops in a heavy, peat-based soil. A gritty mix that will absolutely not support perched water is a good choice.
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1) If you use a pot-in-pot method to remove perched water, the soil in the cache (lower) pot can be finer than the soil in the planting, it can be the same soil or have approximately the same texture as the soil in the planting, or it can be up to 2.2x larger than the soil in the planting. If it is any larger than that, it will "perch" in the upper pot and not drain. The finer the soil in the cache pot, the harder it 'pulls' water from the planting.

2) It doesn't matter what the pot is made of. The drainage is achieved when there is a continuous soil column between the lower & the upper soil. The water 'thinks', because the soil column is continuous, that the soil in the planted pot is deeper than it actually is. Because perched water tables are consistent in height (regardless of container depth or shape) the soil moves down the soil column to occupy what it 'thinks' is the bottom of the main pot. The soil in the cache pot only needs to be as deep as the level of the PWT the soil in the main pot will support to drain ALL the perched water from the planting.

3) Not really. There will be SOME evaporative diffusion as water vapor moves through the soil, but you have to look at the big picture. IF your soil is so water retentive that you actually NEED to employ pot-in-pot to remove the water, you're a WHOLE lot better off with some vapor diffusion from the cache pot than you would be with a PWT in the main pot. The trick is to build a soil that holds NO perched water - then you don't have to worry about perched water in the main pot OR what effect the water in the cache pot's soil might have because you don't need the cache pot.

Al

Oh - very important - I should have added: If you wish to depend on the pot-in-pot method to be effective at anything other than catching excess water or just looking good, the cache pot also needs a drain hole. Filling a cache pot that has no drain hole with soil and nesting a planting in it will not help solve drainage problems.

Al

Guest, some plants are watered in dribs and drabs by some people. But they are people who know their plants and do not wish to have water escape to an ugly saucer sitting under the plant. Such look they cant bear to upset their rooms.

To that though, there are ways to not have to put up with the saucer.
A sleeve.

A sleeve is a pot...a container, that the plant pot sits in...the plant drains properly, the water sits in the sleeve under, and away from the drainage holes.
Most times these sleeve pots are decorative, are made from brighter materials that enhance a room rather than the ugly.

About winter. Plants, whether they go dormant or not, they do slow down because of the loss of light that supports growth. Blame it all on the planet's being at a 23 tilt...it spins on its axis and the sun goes south.
March 21st, the spring equinox...the sun improves and supports growth in the northern hemisphere.
Until that time, plants use less water because they are not growing, or growing at a slow pace.
They don't need water they cant use./

So during these cold dreary months, we give our plants only as much water as they can use...which is much less.
Its a case of giving water when they need it...and not so often.

We still let the plant tell us when they need water, not when we think to water. Never put a plant on any schedule ...don't let the calendar decide, let the plant decide.

The whole reason we water is to provide nourishment by way of the water, to the roots. Giving the soil little water at a time, does not provide water to the roots...or if you water a little every day, maybe the roots are already well sotted...and further water sits at the roots, and eventually causes rot.
The lower leaves are the first sign of trouble.

I'm not familiar with this term 'sleeve' as an outer pot. If I understand the post correctly, I believe the term I commonly hear is a 'cache pot', a decorative outer pot, mostly as an aesthetic consideration.

Normally I just use plastic or clay pots, the plastic either terra cotta colored or green, or the clay pots (I grow lots of succulents), unglazed terra cotta. (Generally, I'm a fan of showcasing the plants alone w/out the distraction of a decorative pot.)

I do however, use several ornamental glazed ceramic pots as cache pots. Most are empty & I guess I water to just before overflow.

However, I have cache pot I only use for Aralias, which benefit from humidity trays. So inside the cache pot I keep the plastic lid of a pint of ice cream, which I keep full of rocks, & I water to slight overflow, so that the planted pot sits ON TOP OF, not in the the wet rocks. Seems to keep the plants happy.

Lately, as I don't currently have any Aralias, I'm using the same arrangement (of cache pots & wet rocks) for some ZZ plants & they seem happy.