I spent some time working for an indoor plant maintenance company.
We fertilized from March to October only.
Plants seemed to do fine on that schedule.
I do the same with my home plants and it doesn't seem to keep the flowering ones from flowering.

Thanks plant lady, I shall carry on the way I have been then
Kind regards

Do plants use nutrients during the Winter? Yes.

Does your potting mix allow you to water properly without the accumulation of salts? That's the question.

If you use a free-draining mix, then reduced doses of fertilizer are recommended.

Josh

Josh, I use a free draining mix. How often would you recommend feeding?

I'd say it depends on the level of daylight. If you live where you have good daylight and some sun, you can always give a little fertilizer in winter months. I live north of the polar cirkle, and at the darkest we have only a couple of hours of "daylight" and no sun, so I don't fertilize untill the sun comes back in february-march.

Plantlady - my comments aren't aimed at you; rather, they're aimed at many current 'conventions'.

I agree with Josh. In MANY cases, conventional wisdom is focused more on helping you to not kill your plant than helping it realize as much of its potential as possible; and, this is one of those cases.

Let's start with the fact that in nature, no one stops fertilizing or removes the nutrients from the soil during the winter. Then, let's examine what this advice, 'that you shouldn't fertilize in winter' is all about, and it's all about what Josh alluded to - soil choice.

Soils that force the grower to water in small sips in order to avoid their remaining soggy for extended periods and interfering with root function or causing root rot, ensure that fertilizer salts not used by the plant and salts from tap water remain in the soil. As the level of salts increases to untenable levels, it becomes increasingly difficult for the plant to take up water. So IF you are using a very water retentive soil, you SHOULD follow the advice to not fertilize during the winter, because the advice protects the plant from the grower's actions and choices.

A second serious problem associated with water retentive soils centers around both soil AND fertilizer choice. If you're using a fertilizer whose NPK ratio doesn't closely mimic the ratio at which the plant actually USES the nutrients, the ratio of nutrients in the soil can very quickly become skewed. A plant uses about 6X as much nitrogen as phosphorous, so if you're using say the popular "houseplant" fertilizer 10-15-10, the plant can't possibly use all that P. It remains in the soil, creating a host of problems, and the more you fertilize, the worse things get. That is, if you're using a soil that forces you to water in small sips to avoid root rot or suppressed root function.

Looking at the advice from the point of view of someone who uses a soil that allows you to water correctly, you have to ask, "What's all the fuss about?" When you can and do flush the soil as you water, you eliminate the build-up of salts AND the skewing of fertilizer ratios that inspired the advice aimed at helping you protect yourself from ..... well, from yourself. Flushing the soil when you water and fertilizing at low doses all winter long is like hitting the fertilizer 'reset' button every time you water.

What are broadly considered to be houseplants don't go dormant in the winter. Most enter a light and sometimes temperature induced torpid period called quiescence, during which they still use nutrients to grow slowly and keep their systems orderly. Ideally, you would have enough of every nutrient in the soil to stave off nutritional deficiencies, but no more. This is very easy to do when using a soil that allows you to water appropriately, but virtually impossible to do with a soil that forces the grower to water in small sips.

When conventional advice is appropriately qualified, we get the opportunity to see it isn't always good advice. By not fertilizing during the winter, you might gain the benefit of not killing your plant, but there is a downside. By using a soil that allows you to water and fertilize correctly, from the plant's POV there is only an upside.

Al

This post was edited by tapla on Sun, Nov 23, 14 at 21:38

I advise my staff (another indoor plant maintenance company) to feed on a much reduced basis over the winter.

I've detected the symptoms of feed deficiency in plants over the winter, but never thought "this plant is being fed too much".

As we put feed in the watering can, and watering is much reduced in the winter, putting c. 50% of the feed in each can means the plant is getting (let's say)

I feed my African violets and my orchids in the winter.

Even under lights, my plants are also maintained over winter with somewhere near 1/4 the amount of nutrients in the soil as they get when light & temps promote robust growth. The important part for a grower is being ABLE to manage almost exactly what's in the soil from one watering to the next so the o/a salt level (EC/TDS) never rises to levels that should be of concern, and the ratio of nutrients never gets out of proportion. These are both conditions that, on the wrong end of the deal, have tremendous potential to limit plants, and they cause a considerable number of casualties every winter. Predictably, the incidents of salt-related issues will pick up after the first of the year and get progressively worse until spring. Unfortunately, stopping all fertilizing, in itself, isn't enough to ward off the limitations associated with accumulating salts in the soil. If we can't/don't flush the soil with some regularity, the salts will build and the severity of the limitations will keep pace in a direct relationship to the accumulation.

Al

Thanks everyone and in particular Al for taking the time to explain the whys and wherefores. I shall take the advice and start feeding my plants during the winter
Kind regards and thanks

Please do keep in mind that if you're going to feed all winter, it's essential that you are using a soil that allows you to flush the soil with each watering, or at least monthly. If your soil doesn't allow you to water to beyond the point of saturation w/o having to worry that the soil will remain wet too long, it's better to avoid the soggy conditions and deal with the nutritional issues than chance fungal root infections. I just wanted to make sure that point is clear in your mind so there are no regrets to deal with later. ;-)

Al