Compost vs fertilizer???

[Emmdemeester]

So I've never used fertilizer in my life. But this year I decided to plant in plastic buckets because we move so Much and always have to restart with the garden. I figured this way I can take my garden everywhere with me! Since I planted in buckets I've read I should be fertilizing. So I'm wondering if I can use compost instead?

I used an organic mix compost about a ratio of 8:1 potting soil:compost in the pails then after everything was planted i sprinkled some mushroom compost on top before I watered. I read just putting compost on top is effective as it the nutrients will go down to the roots with the water. Is this correct? Was my ratio okay of potting soil and compost?

I don't want to fertilize if I don't have to, but I know my plants will need the nutrients. Can I add compost and have the same affect as fertilizer? If so, how much compost should I be adding over the summer? Can you use too much compost and mess up your plants from too may nutrients? Any info on this topic is greatly appreciated! Thanks!

[JONA]

Hi Emmdemeester,
For most small plants what you are doing will be fine.....but....although potting compost will carry most of the nutrients the plants need...mushroom compost will not.
Most mushroom compost is straight from the mushroom beds after harvesting and although it is pretty 'clean'through the composting process the mushrooms themselves will have used up most of its nutritional value. It just makes a great water retaining and soil conditioning product.
So, any larger plant is going to struggle in a container unless it gets some form of feeding now and then.
This can be by straight fertilisers or organic additives like concentrated seaweed etc.
Smaller shrubs will probably get by with annual top ups of good quality compost...although they may need to have some of the top soil removed now and then to make way for the replacement.
Like all plants that spend their lives in pots you have to be on the lookout for any deficiencies that may appear. Flowering or fruiting plants will have higher potash requirements and magnesium and iron deficiencies may hit larger leafed plants.
Just watch carefully and enjoy.

[applestar]

What is your issue with fertilizer? Your plants need nutrients to live and grow and especially if you expect them to produce flowers and fruits, they need more than just enough to survive. They can't make something out of nothing.

Depending on what kind of compost you are talking about, the amount of nutrients is negligible, though there are ways to increase their nutrient value. Store bought Mushroom compost, as JONA explained is spent after the mushrooms have taken most of the available nutrients.

If you want to do your own research, there are certainly ways to supply at least some of their nutrient needs without buying and using what is called "fertilizer". Are you giving them anything at all currently? During the winter when I have all my freeze sensitive plants in the house, I rinse beverage containers with water and dump the rinse water in empty beverage jugs to water with - milk, juice, soda bottles - I add rice and beans rinsing water, pasta cooking water (no salt), put in banana peels, and other fruit scraps, cooked eggshells, used coffee grounds and tea bags, leftover cold coffee....

I also put earthworms in every container -- both the compost eating red wigglers and soil digesting night crawlers.

I keep a vermicomposter going -- so I always have more little baby worms and also to use the vermicompost/worm casting. Bokashi fermenting is another way you can use your food scraps to make nutrient dense plant food.

I make AACT -- actively aerated compost tea.

--- doing all this lets me get away with not using much fertilizer,, especially since most of the plants are in hibernation state during the winter and not actively growing. BUT they seem to need more when they are in active growth. And when I notice signs of deficiency, I use organic fertilizers appropriate for the type of plants.

[rainbowgardener]

No compost is not the same as fertilizer. A good organic fertilizer will have NPK numbers of something like 4-5-4. (By contrast synthetic fertilizers might be anywhere from 10-10-10 to 20-20-20.) Compost is at most 1-1-1, meaning 1% nitrogen, etc. AND the NPK (and usually other nutrients) in organic fertilizer is in a form where it will quickly be available to the plants. The nutrients in compost aren't available until the compost breaks down more (which is why applestar puts worms in her pots to help with that break down process).

Growing in the ground, we use compost because it improves the soil texture and moisture holding capacity and drainage AND along with the small amount of nutrients, it adds a lot of beneficial micro-organisms and macro-organisms (e.g. earthworms) which help the plants use the nutrients both in the compost and in the soil, and help break down all the organic material we add in the form of mulch, etc. And growing in the ground it doesn't matter so much that the percent of nutrients is low, because you can add compost by the shovelful, where as you have to use synthetic ferts by the spoonful or they will burn plants.

But you can't put more compost in your pots, because it is too heavy/ dense and will pack down and exclude oxygen. Pots dry out fast so have to be watered more, but every time you water you are flushing nutrients (especially nitrogen, which is the most transient) out of the soil. So yes, you will have to fertilize your plants in pots. Just look for a good organic fertilizer that has trace nutrients as well as the NPK and has micro-organisms.

But you said you are using potting soil with compost added. Does your potting soil not come with MiracleGro or something already in it? I find it hard to find any potting soil commercially that doesn't have fertilizers. If it has M-G in it, you won't need to fertilize for the first couple months.

[Emmdemeester]

Thanks for everyone's replies!

Just to be a bit more clear, I'm not talking about house plants, just vegetables.

So far I've just put a bit of compost in with the potting soil. I didn't want to put any in because I read that it needs to be nice and fluffy for drainage, but the guy at the green house who sold me the potting soil said it would be a good idea to put some compost in as well. I am sure the potting soil has fertilizer in it, most bagged soils come with enough nutrients to feed for a few weeks to a few months.

It's not that I have an "issue" with fertilizer, I just don't know much about feeding a garden so I was wondering if compost would be as effective, as it is definitely the more natural of the 2, so if it would have been just as effective I would prefer to use compost. But if it's not the same I would just use an organic fertilizer. No problem.

The reason I used mushroom compost is because I went back to the green house as I ran out of compost and I asked for a small bag. The girl brought me that and said it was the smallest bag they had and I had a feeling it wasn't good but my kid had already had enough and I had to get out of there quick so I just took it. I didn't mix any of it in to any of my plants though, just sprinkled it on top. So it shouldn't be a problem right? And I plan to use these year after year so I'm sure the bit of compost inside won't be too bad. I hope anyway.

At the end of the day I'm sure I'll get some vegetables whether I do things right or not and I'm just experimenting. My moms always been the type of gardener to just throw the seeds in the ground and water and nothing else, so that's all I knew. Until I started doing my research over the winter I had no idea about 3 sisters planting, setting a trellis up for your peas, how to prevent your tomatoes from splitting etc...so I have just learned so much stuff, I'm kind of in experimentation mode here I'm sure I won't get it all right this year but that's ok. I'll continue learning!


One more question! Is it pretty hard to over fertilize or is this something I really need to be careful with?

[imafan26]

It depends on the fertilizer. Most of the organic fertilizers have very low numbers and only a part of the nitrogen will be available to the plants immediately. Organic fertilizer needs to be converted by soil organisms to a form that is useable for the plants

Synthetic fertilizers, on the other hand, are ready to use. They are already in a form that is readily taken up by plants. The numbers are generally higher than organic, but there are some slow release fertilizers out there. Because of the higher numbers you do have to be careful not to over fertilize or you can burn your plant or in the case of seeds, may keep them from sprouting.

Fertilizer should be applied around the edges of the pot except for the foliar types like MG, fish emulsion,
AACT and kelp which in diluted form can be applied to the leaves.
You should only give the plants what they need and not over do things. Too much nitrogen on tomatoes and other fruit bearing plants will give you leaves at the expense of fruit. Too much of one nutrient can suppress another.

I don't have luck awith compost or manure in pots. It always results in dead plants for me. Manures are too strong except in tea form and compost just holds too much water and kills plants. Other people don't have that problem but they are using different sources for their composts and they may not have the heavy clay soil that I have.

[rainbowgardener]

Vegetable plants are just plants and still need nutrients to grow and produce.

The mushroom compost won't hurt anything, it just doesn't add a lot of nutrients.

Organic fertilizer will be fine, it just will need to be done a little more frequently. You have to understand that growing things in pots means that you have to fertilize regularly, since the only nutrients they get are what you provide and you are constantly washing them away with watering. Plan on fertilizing once or twice a month.

You didn't answer my question about whether the potting soil has Miracle-Gro or something like that in it. If so you don't want to be adding much fertilizer on top of that at first.

I agree with imafan that compost and manure don't work well in containers, because of bad drainage and packing down. But 8:1 should be OK. If you notice your soil staying wet, you can (gently!) mix a little perlite or vermiculite or sand in for drainage.

[Emmdemeester]

Vegetable plants are just plants and still need nutrients to grow and produce.

The mushroom compost won't hurt anything, it just doesn't add a lot of nutrients.

Organic fertilizer will be fine, it just will need to be done a little more frequently. You have to understand that growing things in pots means that you have to fertilize regularly, since the only nutrients they get are what you provide and you are constantly washing them away with watering. Plan on fertilizing once or twice a month.

You didn't answer my question about whether the potting soil has Miracle-Gro or something like that in it. If so you don't want to be adding much fertilizer on top of that at first.

I agree with imafan that compost and manure don't work well in containers, because of bad drainage and packing down. But 8:1 should be OK. If you notice your soil staying wet, you can (gently!) mix a little perlite or vermiculite or sand in for drainage.

I'm not sure if it has miracle grow, but the package does say it has a bit of nutrient in it to get it through getmination and such. I'm not sure what it is though. I'll have to read the package more closely.

So if I just use an organic fertilizer 1-2 times per month, that won't be too much?

[rainbowgardener]

So if I just use an organic fertilizer 1-2 times per month, that won't be too much?

NOT too much. Remember the plant is totally dependent on you for nutrients and you are constantly washing them away.

[Emmdemeester]

So if I just use an organic fertilizer 1-2 times per month, that won't be too much?

NOT too much. Remember the plant is totally dependent on you for nutrients and you are constantly washing them away.

Thanks for the help

[toxcrusadr]

I kind of like the time-release beads, you can scratch them into the surface and they dissolve just a bit every time you water. I can't remember the product name but they come in a clear jug.

Mainly you should keep an eye on your plants and they will tell you if they are short on nutrients. Leaves pale? Probably need some nitrogen. But that shouldn't happen very soon with the stuff you planted them in. If they grow bushy and green with no fruit, you used too much nitrogen. A balanced fert for potted plants is best - it should have NP and K and the N won't be real high for veggies. 29-3-3 lawn food is definitely out! :-]

[Gary350]

Farmers never compost 2000 acres fields like gardeners do but they do plow under old crops, think about that. Compost has almost no food value for plants but is excellent for root growth it softens the soil. I buy fertilizer in 50 lb bags at Farm Supply Store they last me about 5 years in my 35'x60' garden. If your planting in buckets 50 lbs will last you 30 years you should buy smaller amounts. If your using potting soil it has very little food value for plants you need fertilizer. Tomatoes need very little nitrogen. Peppers, squash, okra, beans, do good with 15/15/15. Corn, onions, garlic all needs lots of nitrogen. Potatoes needs no nitrogen. With no experience with fertilizer do not fertilize until plants are 10" tall, 1 tablespoon per plant per week is fine, when plants are 3 ft tall 2 tablespoons is good, when plants are 5 ft tall 3 tablespoons is fine. When temperature is above 85 degrees F hot and sunny NO more fertilizer all summer. With potting soil in hot weather it will be best to mix soil with water then water plants with muddy water.

[Emmdemeester]

Farmers never compost 2000 acres fields like gardeners do but they do plow under old crops, think about that. Compost has almost no food value for plants but is excellent for root growth it softens the soil. I buy fertilizer in 50 lb bags at Farm Supply Store they last me about 5 years in my 35'x60' garden. If your planting in buckets 50 lbs will last you 30 years you should buy smaller amounts. If your using potting soil it has very little food value for plants you need fertilizer. Tomatoes need very little nitrogen. Peppers, squash, okra, beans, do good with 15/15/15. Corn, onions, garlic all needs lots of nitrogen. Potatoes needs no nitrogen. With no experience with fertilizer do not fertilize until plants are 10" tall, 1 tablespoon per plant per week is fine, when plants are 3 ft tall 2 tablespoons is good, when plants are 5 ft tall 3 tablespoons is fine. When temperature is above 85 degrees F hot and sunny NO more fertilizer all summer. With potting soil in hot weather it will be best to mix soil with water then water plants with muddy water.

Thanks for the tips! So you're saying I shouldn't fertilize yet since I just planted? A couple of my tomato leaves are starting to look yellow Ish. I thought it might be from lack of nutrients (someone else told me when the leaves are yellow they need nitrogen). They definitely aren't 10 inches high yet.

And if I stop fertilizing when the weather gets hot, how would my plants get nutrients? I guess I don't understand why you have to stop when it gets hot.

Thanks!

[imafan26]

You should fertilize when the plants are actively growing. Yellowing can mean too much water or the soil is not drying out between watering (my issue with compost in pots). Yellowing on the bottom with green leaves on top usually mean their is a lack of nitrogen. When it turns very hot a lot of plants will not be growing and they will try to conserve water any way they can which is usually by wilting and dropping flowers and fruit in the heat. You feed plants when they are growing but not when they are dormant or in distress.

When the weather gets hot, you have to make sure the plants have enough room in the pot so the soil stays moist and the plants don't wilt in midday. I still feed my plants but usually when summer rolls around, the plants are already fruiting and they have a limited life after that so, I don't feed them as much, but I make sure they get a lot of water. I usually feed my plants when the true leaves appear, when the first flowers show and when the first fruit come out. After that, I feed the plants monthly until they are done. Most of the annual veggies like beans, cukes, bell peppers, and leafy greens mature between 21 (radish)- 100 days for squash. Once they start fruiting, most will give fruit for about 6 weeks and die. Tomatoes are the exception as they are perennial in mild climates and it is disease that kill them so I can have the same tomato for 7-9 months if it doesn't rain a lot. In the states, bell peppers last till frost, here I am lucky if I get 3-8 peppers (2 flushes) before they are gone. The frutescens, baccatum, and chinense peppers can live here for years.

[Emmdemeester]

You should fertilize when the plants are actively growing. Yellowing can mean too much water or the soil is not drying out between watering (my issue with compost in pots). Yellowing on the bottom with green leaves on top usually mean their is a lack of nitrogen. When it turns very hot a lot of plants will not be growing and they will try to conserve water any way they can which is usually by wilting and dropping flowers and fruit in the heat. You feed plants when they are growing but not when they are dormant or in distress.

When the weather gets hot, you have to make sure the plants have enough room in the pot so the soil stays moist and the plants don't wilt in midday. I still feed my plants but usually when summer rolls around, the plants are already fruiting and they have a limited life after that so, I don't feed them as much, but I make sure they get a lot of water. I usually feed my plants when the true leaves appear, when the first flowers show and when the first fruit come out. After that, I feed the plants monthly until they are done. Most of the annual veggies like beans, cukes, bell peppers, and leafy greens mature between 21 (radish)- 100 days for squash. Once they start fruiting, most will give fruit for about 6 weeks and die. Tomatoes are the exception as they are perennial in mild climates and it is disease that kill them so I can have the same tomato for 7-9 months if it doesn't rain a lot. In the states, bell peppers last till frost, here I am lucky if I get 3-8 peppers (2 flushes) before they are gone. The frutescens, baccatum, and chinense peppers can live here for years.

So I should be letting my plants dry out before watering? I have been watering every day as I thought it was good to keep them kind of damp at all times. Hopefully I didn't mess anything up!

[rainbowgardener]

That would be why they are yellowing. Different plants have different requirements and you haven't really told us what plants we are talking about. But in general, you should wait until at least the top inch or two of soil is dry before adding more water. Every day watering is almost surely too frequent, unless your containers were filled with sand, instead of potting mix.

[applestar]

Two ways to tell when to water average plants --

Thoroughly water, then allow to drain completely, removing any water pooled in the catch tray after 15 minutes. Then heft the plant pot and learn how heavy it feels when fully watered.

When it needs to be watered again is variable depending on type of plant, how much it is growing or fruiting, type of potting medium, size of pot and root mass. Weather/climate conditions. Do NOT water on schedule especially if weather has changed, plant development has altered, etc.

The plant needs to be watered again when the pot feels lighter. Especially with plastic pots, it will feel somewhat top-heavy and there is weight missing from the bottom/soil. At that point, water thoroughly again.

Another way to tell is to feel the surface of the soil -- and a little way deeper. First press your fingers flat on the surface. If damp/moist and potting medium sticks to your fingers, no watering necessary. If surface feels dry, wiggle your fingers a little way down -- depth depends on size of plant and type of plant. I usually feel at least first knuckle down past fingernails for small containers. 2nd knuckle for big containers.

[Emmdemeester]

That would be why they are yellowing. Different plants have different requirements and you haven't really told us what plants we are talking about. But in general, you should wait until at least the top inch or two of soil is dry before adding more water. Every day watering is almost surely too frequent, unless your containers were filled with sand, instead of potting mix.

Sorry, I thought I had listed everything but now I see that I listed everything on a different post of mine.

From seed:
- carrots
- beans (purple pole, green and yellow bush)
- peas
- spinach
- kale
- beets

Transplants:
- Roma tomatoes
- rapunsel baby tomatoes
- spaghetti squash
- bell peppers
- pumpkin
- bush pickling cucumbers
- corn (I have read it doesn't transplant well but I wasn't going to plant it at all, I just saw them at the green house and decided to experiment. They seem to be doing the best of all my plants)

If it helps I live in Saskatchewan Canada and I planted 11 days ago.

I think this is everything. The tomatoes aren't really turning yellow, there's just maybe 3 leaves that were slightly yellowing but I started to let the dirt dry out between watering and they seem to be doing well. I was watering daily to keep the germinating seeds moist but now that everything has sprouted I've also let them dry out a bit between waterings.

Should I be fertilizing soon?

[imafan26]

Start fertilizing when the true leaves appear. Before them, the seed will provide for all the plant needs. I would suggest you use a water soluble fertilizer unless you want to go only organic. You can try fish emulsion and AACT,

[toxcrusadr]

Kind of off topic but it was mentioned that mushroom compost doesn't have a lot of nutrients. I wanted to chime in with ONE lousy data point that disproves this. :-]

I had a dozen locally available bagged compost products tested by a lab a few years back. One was a mushroom compost. The median NPK of the whole group was 0.8 - 0.2 - 0.2
The mushroom compost was 1.7 - 0.8 - 1.2

In fact, that particular bag of this product that year had the highest P and K of all the products tested, and it was beat on N only by my home made compost which was 2.7% N.

Products vary, but I would not hesitate to use mushroom compost if I could get my hands on it.

[imafan26]

Watering should always be as needed. Some plants like to dry out between watering like cactus and some of the gray leafed Meditteranean herbs. Other plants like even moisture. Different plants different needs.
What is important is for most plants is that you have a well drained soil, few plants like soggy feet

Some plants want an average to poor soil like lavender and sage
Other plants need a rich soil like most of your vegetables, fruits, and tropicals.
Plants that come from areas of the world where it is near desert conditions have evolved to conserve water so they need to be watered well, but allowed to dry between watering. These plants usually like a more neutral to alkaline sandy soil in full sun. They often will have dormant periods which coincide with the fact that where they come from will have a dry season. They will usually get through it by going dormant. During dormant times you don't want to feed and you should reduce watering.

Plants that come from the tropics usually don't have a lot of issues with fungus. They are designed to capture water and funnel it to the roots. In deep dark jungles leaves are big to maximize light capture. Soil is rich with humus and the air is humid. Plants are used to getting a lot of water Jungles are crowded so there is a lot of root competition for water and only the top few inches have most of the nutrients from the fallen leaves so roots are close to the surface. These plants will only bloom rarely so need more nitrogen but not a lot of phosphorus.

Vegetables for the most part want a rich well drained soil with at least six hours of full sun. Since herbs and vegetables come from all over the world, the soil conditions they like vary.
Leafy greens like lettuce like a lot of nitrogen but moderate users of phosphorus
fruits like papaya and banana are rich sources of potassium, so the plants need to get more potassium
root crops need less nitrogen, otherwise they make more leaves and less roots. They need a low nitrogen, higher phosphate fertilizer and do better is the soil is more neutral and less acidic
Most other vegetables like a slightly acidic soil. Nitrogen should be given in divided doses, not all at once

The way nitrogen works, it is very volatile, nitrogen fixing bacteria will fix nitrogen from the air when they associate with a legume plant. However, other bacteria in the soil are denitrifying and release nitrogen that is not held in their bodies or the plants back to the air. That is why most soil test do not give you nitrogen results, because it changes too fast. It is also why even if your soil is high in just about everything, there will still be a nitrogen recommendation. If you have lush green leaves, you have a lot of nitrogen. If the plants are small and pale, you don't. Nitrogen is usually the primary limiting factor of growt

When you prepare a garden bed it is important to incorporate all the immobile elements. This is when you add your complete starter fertilizers, organic fertilizers, and add sulfur or lime to correct pH. You should ideally do this 4-6 weeks before you plant, but most people don't plan that far ahead. Aim for at least 2 weeks ahead. Seeds have all the nutrients they need to get the young plants through the first couple of weeks of life. They need to be fed once the true leaves appear.

Too much nitrogen in the seed bed can lead to failure of the seeds to sprout and dampening off. The first nitrogen feeding should come after the true leaves have come out. 1/2 of the nitrogen allotment shoulc be scratched into the soil and watered in. Be careful not to get fertilizer on the leaves. Nitrogen left on the surface will be lost sooner. When the plants are about 4 weeks old the next 1/4-1/2 of the nitrogen should be given. I usually give 1/4 and give the rest in monthly doses. The largest nitrogen demand is in early growth when the plant is putting on leaves, the next is when the plants have reached full size and start to flower or bulb up. After that some nitrogen is still needed to produce fruit, but not a lot.

It really would take the guesswork out of what kind of fertilizer and how much to use if you just do a soil test. Every persons soil will be different. New gardens especially, have not had the time to build up organic matter (it takes about 3 years), and you may have to amend the pH of your soil or be very selective about what you grow.

Watering also depends on not only the plants, but on what kind of soil you have and how fast it drains and dries. That is why the best advice you can get is not to water on a schedule but as needed. If you have a hard time figuring that out, get a moisture meter, it helps, but it would be cheaper just to use your finger and poke the soil and see how moist it is and look at your plant. If it isn't wilting yet, it can go a little longer. If it is really wet and your plant is sickly and yellow, you may be watering too much.

[toxcrusadr]

The idea is to not have them soaking wet all the time, but don't let them dry out so much that they wilt. Happy medium.