angiecis
Full Member
Posts: 18
Joined: Tue Mar 07, 2017 6:38 pm

What type of fertilizer?

Howdy!

I was wondering what type of fertilizer everyone uses in their container gardens?
Especially for herb/vegetable gardens!!

I think I need to try a new fertilizer. :wink:

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ElizabethB
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Posts: 2105
Joined: Sat Nov 24, 2012 12:53 am
Location: Lafayette, LA

Hi Angiecis,

Welcome to the forum.

Fertilizer discussions can be very complex and scientific.

Fertilizer is not food. Plants produce their own food. Think of fertilizer as vitamins.

To keep it simple look at the label on the container/bag. There will be 3 numbers - NPK. Nitrogen, phosphorus and potassium. An all purpose fertilizer for container gardening will have a ratio of 1-3-1

(3-9-3 or 8-24-8)

Granular is the least expensive but the most likely to cause damage due to improper application. The nutrients are released very quickly.

Water soluble is a good option - the nutrients are released quickly but need to be re-applied more frequently in containers because they are flushed out by watering.

Slow release is the most expensive option. The nutrients are released slowly over a period of time. A good option for containers.

Brand does not matter.

Decide how you want to apply the fertilizer - granular, water soluble or slow release - then find one with a 1-3-1 ratio of NPK.

Good luck.

imafan26
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Posts: 13961
Joined: Tue Jan 01, 2013 8:32 am
Location: Hawaii, zone 12a 587 ft elev.

People have their preferences. Some want organic soil, seed and fertilizer. It is very difficult to do organic in small pots.

I like to use a slow release osmocote in my planting mix for a long slow feed (3-6 mos) and depending on the plant I will supplement.

Acid loving plants like citrus, tomatoes, blueberries, and gardenia get citrus food that contains micro nutrients as a supplement

I have only a few alkaline loving plants ( mostly root vegetables,) they need to be in the alkaline soil of my alkaline plots and need to have low nitrogen.

Plants grown for their leaves like a higher than average nitrogen and low phosphorus.

Fruit trees need low nitrogen but a higher potassium.

I think of composts as food for the soil but fertilizer as food for the plants. In my garden I do use compost but I do not like to use animal byproducts in the garden so I feed my plants synthetic fertilizers according to my soil test. According to my soil test all I need to add is nitrogen. I use a very small amount of sulfate of ammonia and it is usually applied in divided doses. The first will be when the plants are about 2 weeks old and the next around 6 weeks when they start to flower and monthly until they are done.

In pots I use mainly citrus food with either MG or peat lite with osmocote since I have strawberries, tomatoes, blueberries, eggplant, and peppers in pots and they like a slightly acidic mix.

For plants that like a low nitrogen environment, I use a more alkaline mix of potting soil (MG potting soil) with a couple of handfuls of vermicompost, and a couple of tablespoons of 10-20-20 fertilizer per 5 gallons of mix. (Root crops beets, carrots, daikon, ginger, and taro. I don't have issues adding vermicast but compost causes problems in my mix as it holds too much water.

You can use any good potting soil. I use MG because it works well. The organic ones and the ones that contain compost hold too much water for me.

When you plant in containers you have to see the big picture. You need to provide the right soil, acidic or alkaline, moist or fast drying depending on the needs of the plant. You provide nutrients also based on the needs of the plants. Most young growing plants or plants grown for their leaves need more nitrogen. Plants that usually grow on rocky or calcarious soils like alkaline conditions and well drained soils.

The amount of fertilizer and timing is important. When planting seeds, you don't need a lot of fertilizer. The seed will provide all the nutrients that is needed until the true leaves come out. A starter fertilizer with slow nitrogen is optional. Phosphorus, potassium and micronutrients need time to release. Once the true leaves come out that is when you would give the first supplement of nitrogen. The second nitrogen boost should be just as the plants start to bulb or flower. Longer lived plants would get supplements each month thereafter.

For established plants I give them a semi annual general fertilizer ( osmocote for potted plants, citrus food for in ground plants)
I usually feed plants when the new shoots start to come out again when they start to fruit or flower.

Roses, tomatoes, peppers, and citrus which produce more than one cycle a year get fed when the new shoots or flowers start to show and when they start to bud up.

Now is a good time for me to feed everything since most things now are starting to put out buds and shoots.

In cooler months plants don't grow very much so they usually don't need to be fed, but they should be divided and potted up if it is needed.

I have hundreds of plants in pots. Some have been in pots all of their lives.



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