Tomato plant fertilizer

SweetSerenityFebruary 16, 2012

I'm confused. I bought Miracle Gro's "Tomato Plant Food" with an 18-18-21 mix.

Now, I read in my local paper's garden section that the nitrogen level (the first number) should be a lot less than than the p and p levels. They suggest soluble bloom busters with a 12-48-16 mix or a 10-30-20 mix.

Who should I trust?

Thank you for reporting this comment. Undo

go with a natural fertilizer like fish meal or go with a organic one miracle gro works to but dont over feed the plants but if there seedings not use no fertilizer just spary them with water like you do with in door plants

    Bookmark   February 16, 2012 at 11:27PM
Thank you for reporting this comment. Undo

Studies have shown that a NPK ratio of 2-1-3 (example 10-5-15) is the best for Tomatoes. If you are using mycorrhiza or other beneficial bacteria or fungi keep the "P" (phosphous) below 6. Ami

    Bookmark   February 17, 2012 at 9:00AM
Thank you for reporting this comment. Undo
ralleia(z5 Omaha, NE)

I put a lot of stock in what Mel Bartholomew (Square Foot Gardening) says about growing plants. His basic fertilizer mix for tomatoes and other fruiting crops has an NPK of 2.6-4.9-2.4.

This most closely matches the recommendations of your local paper.

The danger of feeding fruiting crops a lot of nitrogen is that it encourages leafy growth. So you might get a gorgeous green tomato plants, with very few fruits. Since most of us grow tomatoes in order to eat tomatoes (and not just to admire their foliage!), then I would steer clear of the higher-nitrogen numbers.

    Bookmark   February 17, 2012 at 9:10AM
Thank you for reporting this comment. Undo

Thanks everyone for your input.
Ralleia, that's exactly the reason given for staying low on the nitrogen side. I did get a grow spur of the leaves when I used the Miracle Gro. I do have a lot of blooms on them now but I'm thinking I could have had more.

    Bookmark   February 17, 2012 at 12:16PM
Thank you for reporting this comment. Undo
digdirt2(6b-7a No.Cent. AR HZ8 Sun-35)

Since you already bought the MG you can use it but just cut it back to 1/2 or even 1/4 strength. In other words 18-18-21 becomes 9-9-10 at half strength or 4.5-4.5-5 at quarter strength.


    Bookmark   February 17, 2012 at 3:12PM
Thank you for reporting this comment. Undo
Ohiofem(6a Ohio)

Bloom booster fertilizers (with high P) are useless and can even damage your plants. Here's a link to a discussion of why:

Here is a link that might be useful: Why high-P fertilizers are not a good idea

    Bookmark   February 17, 2012 at 7:05PM
Thank you for reporting this comment. Undo

This is for Containers
A 3-1-2 (Miracle gro, Foliage pro) with foliar applications of a 5-0-20 (trisert K+) and keyplex (for extra micronutrients), Epsom for Mg if not in ferts.
Has never failed, and is the best that I have found. High P's are NOT useless, they are for the ground, in a container there are plenty of other things to waste your money on.
For Ground
Mix in Epsom, greensand, and some dolomite. side dress with a 10-10-10, then go from there. If you see an N deficiency, add a small amount of 33-0-0, if low in P correct with 0-45-0, low on K go with 10-10-20. It is all about YOUR conditions, nothing will work for every one, but these are good places to start.

    Bookmark   February 18, 2012 at 10:56AM
Thank you for reporting this comment. Undo

I read in my local paper's garden section that the nitrogen level (the first number) should be a lot less than than the p and p levels.Two observations here:
1. It is the total amounts of N-P-K that is important here... diluting a 20-20-20 by 100 times makes it 0.2% by weight. So putting 10 grams into 4000 ml of water yields a brew of ~1 part fert per 400 or 0.25%*0.20% (0.05% NPK). Rather weak but readily available.
2. Nutrient balance is important for most plants. Consider that most manures (cow, horse, poulty, etc.) contain more total N than either P or K. So I go with that balance unless there is a reason to boost one of the majors (like forcing roses into bloom).


    Bookmark   February 19, 2012 at 7:58AM
Thank you for reporting this comment. Undo

The many conflicting recommendations should tell you something. If many different formulations are suggested, then isn't it logical that it doesn't make a great deal of difference?

You *can* over-fertilize. You *can* burn the plants. But beyond that, my experience is that that healthy plants will take what they need and do well -- the range is wide. I personally like to use organic fertilizers because they tend to be slow-release. For the same reason, I like products like Osmocote.

I grow my early tomatoes in containers and the main crop under black plastic, so especially for the latter, it is very useful to have a long-acting fertilizer. But our growing season is about 5 full months, so I end up pushing a few tomato fertilizer spikes through the plastic after about three months.


    Bookmark   February 19, 2012 at 7:36PM
Thank you for reporting this comment. Undo

I work at Lowes and had a customer today buying tomatoes(Bonnies). His wife asked if we had ammonium phosphate. I showed her some lawn fertilizer we had that was 21-0-0. She told me he was going to use that on the tomatoes. She tells me he's been growing tomatoes for 40 years. I tried to explain to her that high nitrogen is going to give you tomato "trees". Does ANYBODY here use 21-0-0 on their tomatoes?? Not me!!!

    Bookmark   February 28, 2013 at 12:25AM
Thank you for reporting this comment. Undo
missingtheobvious(Blue Ridge 7a)

I was at Lowe's a couple of years ago and saw something organic which was labelled as (Somebody's) "Garden Plant Food." Not a brand I'd heard of.

Anyway, they claimed their "garden plant food" was good for everything -- but the cover of the bag had a photo of a 10" wide tomato from one side of the bag to the other -- no other plant or veggie, only the tomato. The fertilizer was 4-3-2. I don't know if that makes sense for organic fertilizer, but it wasn't what I'd read was recommended for tomatoes.

It seemed so odd that I wrote it down (and actually remembered where I'd written it).

    Bookmark   February 28, 2013 at 12:54AM
Thank you for reporting this comment. Undo

That sounds much more reasonable. At least it's a mix of the big 3. I could put that on tomatoes without too much concern.

    Bookmark   February 28, 2013 at 1:10AM
Sign Up to comment
More Discussions
Supermarket Tomatoes Plants II
Here we go again. I have started 8 more seedlings for...
The Kumato Tomato Thread
There is a litany of information across this forum...
Better than a ziplock bag
Credit: Durgan from Brantford came up with the idea. Pop...
BriAnDaren Ottawa, On Zone 5
Tell me your ultimate tomatoes
Highest yield: Best flavor: Easiest/most disease resistant: Best...
Newbie at grafting tomatoes
I'm completely new to the procedure (also new to Tomatoes...
© 2015 Houzz Inc. Houzz® The new way to design your home™