Are you referring to zonal or windowbox geraniums, Pelargoniums? If so, a gallon sized container is likely too small for optimum growth and flowering. MiracleGro potting soil is also not ideal - it tends to hold a lot of moisture and not drain as well as it should. If you are watering much in addition, the soil may very well be waterlogged, which would account for yellowing foliage.

I prefer to use a fast draining potting soil without any moisture retaining additives or fertilizers. You will need to water on a regular basis using this type of planting medium as well as supply supplemental fertilization. MG fertilizer is fine for this purpose, but I like to dilute it by half and apply every other week. Or use slow release supplement like Osmocote. That will encourage summer-long blooms. And they need lots of sun. Deadhead to remove old flowers.

Hi and thank you for your response I'm not sure what type they are I bought them from seed at HD. They look common to me. The MG they are in is supposed to control moisture and fertilize the plant for up to 4 months.

MiracleGro potting soil doesn't control moisture -- it holds moisture in the soil, often too much, creating a waterlogged situation. Yellowing leaves is a sure sign of too much water. The soil also collapses rapidly, impeding good drainage and eliminating space for oxygen. And I'd be skeptical about the fertilization lasting for 4 months. MG is very fast acting and not a slow release type. Most folks who do a lot of container gardening avoid MiracleGro soil products like the plague.

An unadulterated, good quality potting soil would likely provide much better results - you just supply water and fertilizer as the plant needs it, not when some fertilizer manufacturer thinks it should be applied.

Thanks for the tips, all my Geraniums looked great when they first started blooming, then all of a sudden the blooms died as well as some of the leaves. Recently I transplanted a few to larger pots, dead headed, cut off any Yellow leaves and filled the rest of the pot with Pro-Mix BX and so far the plants seem to be making a come back. Can I fertilize them with regular Miracle Grow fertilizer? the one you attach to the end of your hose? Thanks for all the help. I'm gonna ask this question in another forum too but how do you propagate Geraniums? cuttings? or just wait till it sets seed?

The Promix BX is the best soilless mix for anything from starting seeds to growing plants. It's the only thing I use for all my plants. I agree that your geraniums were being kept too wet. Geraniums definitely don't like wet feet and like to dry out between watering.

Yes you can fertilize with water soluable fertilizer. Every 3 weeks is good for geraniums.

Geraniums can be started from seed or cuttings, but not the seed your geraniums make. They are hybrids and will not come true from their seed. Besides it takes too long for them to make seed and you would cut out your flower production for this summer.

Better to buy seed, but they take a long time to grow into a flowering plant-from January to June-July, so unless you have a light set up or some where to grow them concentrate on cuttings.

Geraniums are actually tender perennials and can be wintered over. If you have a cold cellar they can be set in there and forgotten until spring or you can grow them on a south or west facing window sill. The latter is how I do mine, then I can take cuttings when the branches get too long. I keep them trimmed back and don't allow them to flower. I give them almost no fertilizer and let them dry between waterings. Here's how to take cuttings

TAKING GERANIUM CUTTINGS
First you must make sure everything you use is very clean.
Take your cuttings: With a sharp knife or razor blade cut a 4 or 5 inch piece from the growing tip, cutting just below a leaf. All roots and branches come from a leaf joint. Remove all but the top 3 or 4 leaves. Let your cuttings callus over--Lay them out somewhere on newspaper. Mine sit on my spare room floor. Let them sit for about 5 days. The leaves will look wilted and dead but they're not. The cut end will shrivel and dry. Letting them callus over and watching the water cuts down on blackleg a deadly fungal disease especially to cuttings.
Now plant your cuttings. In a clean pail mix your Pro mix with the water so you make sure the soil is damp right through. You want the soil wet but not too wet. Squeeze a handful and some moisture should come out but not a lot. Fill your pots and make a little hole in the center with your finger or something else that will make a small hole.
Dip about 1/2 inch of the cut end in rooting hormone. It comes in powder or gel, either is OK as long as it's for soft wood cuttings. I use Stim-root NO. 1. After it's dipped put it in the hole and cover it in, and you're done.
Keep the soil moist but not overly wet. They will look wilted at first but that will change as it starts to grow roots. You will know it's rooted when it starts to show new growth.

If you are going to plant it outside right away, wait until it is rooted well before you set it out.

All this complaining about how plants have been given too much water......lets put the blame first on the person growing them....they don't water themselves.
Its up to the person to know when the plant was watered last and whether it needs further moisture.
The finger on either hand is close at hand...no pun...
and is an excellent indicator whether the plant in front of you needs water.

Considering that when we give water it should drain...thus the soil is getting rid of excess. If we don't let it drain properly, then we invite the problems.
That goes too for bedding plants....the ground should drain well--and rain notwithstanding, should be looked at to avoid over-watering.

The deadheading of a geranium is one of the easiest and most rewarding of care that should be given the plant.
Since old, toothless flowers still steal energy, removing the dead or dying just gives back to the plant what can send its energy where its needed or where it will do the most good.

If the plant is at death's door...then there is no reason to not cut it back....severely....and if it still has life in it, it will recover in a few days....bloom anew even.

If the plant looks too far gone, then maybe think to put it into the basement, into a cool, dark, dry environment and let it rest until about the next ides of March when it can be brought back out, cut back as necessary, re-potted, watered and given the best sun.....chances are it will show new life again.

Brought back from brink....that's what geraniums do.

Now aside from how the gardener considers what his selection of soil is, potting soil/potting mix/soiless mix....are all recommended for potted plants.
If the person tends to overwwater--then the soiliess mix is a choice he might make. If he is a constant looking at person, then a potting soil or potting mix is perfectly OK.
As long as the person lets the watering drain well and doesn't let the water sit under the plant to be re-drawn back up, the plant should do well enough.
Some plants require fertilizer...others a little...annuals definitely need to be fed...about every 10 days...3 weeks..and a geranium is no different. They have such limited amount of soil to draw food from, they need regular fertilizing.
A 15/30/15 is the most recommended....and Miracle Gro...by Tradename...is one such plant food.

Whether a particular soil holds more moisture than someone would like....then its up to the person using it to be guided by the soil's ability to not need water so much.
Again, if the plant is overwatered using such soil.......
who's to blame...the person....or the soil.

Goren:
You can use miracle grow if you like, but nothing made by that company will cross my threshold--I have tried their water soluable fertilizer and it's not near as good as other brands that has the same combination of nutrients.

Their seed starting mix is pure peat with nothing to keep the peat loose so it compacts. This new so called moisture control is the worst yet. You may stick your finger in and have it feel dry but there is lots of moisture due to the polymers that are storing water

NOPE--miracle grow is all hype and very poor products

Sometimes it is the fault of the soil mix.

I have used MG in pots and store many of my plants in a cool room.
It would take 2 weeks or more for the MG to dry out before I could even think about watering again, and by then my plants would rot. I can't even plant a citrus in that mix. It was the number killer for my trees, even if I would wait for 2 weeks before the mix would dry out and that is with proper drainage. Of course for my area and my conditions, any mix that held moisture to long was not good.

So I have managed to find a way, make my own mixes that are much more coarse and do not compact over a brief time. They also do not break down rapidly which allows me to water more often without fear of a mix that is to retentive on the water.
My mixes dry out within a few days even in cooler conditions and lack of sunlight.

I also want to thank you Goren , Oilpainter and others for such great and helpful/useful information! I have been lurking here for a while and you are all so very helpful!

Mike

Catching up to this thread January '11....but its a message others might heed now that the over-wintered geraniums are soon coming out of storage.
I, personally, don't use named-brand soil, I use the soil that I find in nurseries and I test it by poking a finger into the bag and take some into my hand.
But I am still one that does not blame the potting soil uness its one that turns to cement the first time you water it. And there are those out there...usually the inexpensive ones--more clay than anything.
I also like using peat moss for improving the texture of soil, it improves the soil's ability to take in moisture and oxygen. Since the pot has so little soil and its supposed to feed the plant, what can hold moisture is always appreciated. Some potting soils I admit are heavy in peat moss and may hold too much moisture too long.
But, its still the person who is watering the plant decides how much is given.

A gallon container as the writer says is being used...we are not told how large the plant is...a gallon is a major size pot...one wouldn't use it to bring along....say..an AFrican Violet...there's too much soil for so little plant.
That's the history of using too large a pot for small plants...there is just too much soil the roots are being told to venture out into...too much food is being drawn in.
As much as we starve a plant, we can over feed it.

A plant should be given the size that fits the roots...and when it grows we go up one size only..which implies no more than 2" diameter of the pot.
The size of the pot is best considered when we first pot up a seed....or seedling. We don't throw them into a gallon pot...they wouldn't last a week in such size.

Watering is the one thing...add up all other reasons why a plant has problems, and you wont come up with the number having trouble due to watering.
Then too, the temperature of the water can have a lot to say. Plant water should be let sit overnight to gain room temperature. Tap water straight out should be avoided.
Then too, if the water comes from a softening system...that can cause immediate problems.

Yellowing leaves suggests over-watering is the amin culprit...and overwatering makes the culprit the person doing it.

Yes, they can die in MG and in pots too small, especially if root bound.
That is what is happening to one of mine as we speak.

I would give them room to grow and skip the MG all together. I plan on putting mine that is doing poorly in a mix that stays wet too long into a fast draining gritty mix and I can't wait!

If you are loosing your plants, then I would consider using a very open, porous and well draining mix, then the pot size will not matter, and you can feed and water as often as you want without fear of rot and or salt damage which is usually the main culprist to the health of plants, especially this time of the year.

An open and very fast draining mix which allows you to fertilize all year and encourages extra waterings is something that plants require and would appreciate a lot more than any peaty mix that disintegrates very rapidly over time and that does not allow you to water frequently.

Mike

Mike, if you know anything about sizes of pots, you wouldn`t advise a new pot-growing gardener to use `whatever size she wishes`. Size does matter.
When roots need nourishment, they venture out into the surrounding soil. Trees also follow this rule.
If they have to go too far afield then the plant becomes weak, lanky and shows no vigor.
The size of pot should reflect the size of the plant and the roots. Why do we use small pots for African Violets...wouldn`t it just be good enough to use larger pots...put two or three plants into one...make a bigger show.
Well, of course, we don`t do that....same goes for other plants.
And when we choose to transplant to a bigger pot, its because the soil has been worn out, and the plant needs room to grow more. Up one size only is the rule.
Go up further than that, you risk the health of the plant.

Any research site on `size of pots for houseplants` will confirm this and say it better than I could ever.

Hi Goren.

Thanks for that. I guess I should of told you that I do "not" grow in that type, or maybe the kind you use, soil mix that limits my plants ability to thrive in what ever size pot I use. Sorry about that.

In many ways, if one chooses to grow in a mix that breaks down very quickly, such as bagged mixes or even amended bagged mixes, you are right, it will be worn out rather quickly, and most plants sitting in that type of mix bigger than a pot that is just right for them, could take longer to dry out, and maybe even cause root rot and fertilizer issues, which in many cases, many have to deal with.
Therefore, there is where the operator error comes in, and the type of mix being used. I like to think what a person chooses for a mix in the beginning will determine how limited they are in growing their plants.
It is very easy to over water in these bagged, fine particle mixes, and in particular, my geraniums would either die of rot in containers to big, or die of compacted roots in a pot that has filled with roots. Both will also limit nutritional uptake.

On the other hand:

I use a mix that I myself make in which is durable, long lasting, does not compact, and evenly dries out within a short period of time.
That would be a gritty mix, or a 5part bark, one part perlite, and one part peat which will breakdown a bit quicker than the gritty mix.
In these mixes, all my plants do very well in any size pot I want, in fact better, because this allows very healthy roots to roam even further, encouraging good top growth.
I have some plants that if I was using bagged mixes, would have to be in a 4 inch pot, but they are in 8inch and higher because I have them in a gritty mix, and they are thriving.

That being said, I also will be planting my geranium in a grittier mix that I make without peat, into a much bigger pot to encourage good top growth and it will allow me to keep that plant in the same container for at least three years.

I really appreciate your time, and I must say that you seem to have much knowledge and experience in geraniums, and I enjoy what you have to say about them.

If I should ever decide to go back to bagged mixes, or any kind for that matter that has very fine particulates, then I will take your suggestion about potting up or down very seriously.

Nice chatting with you and thanks for caring.

I have a question? If the size pot really matters, then why do plants in the ground do so well in proper soils with no limit to how far the roots can roam?

Here is an article about how soil works in containers. Enjoy:-)

Mike

Here is a link that might be useful: Containers soils, fertilizer and water movement