Tomato Fertilizer

Just went to Home Depot this evening and noticed a 5-15-5 fertilizer for citrus and palms. Would this be OK to use for my tomatos? If not -- What would you suggest? What was your experience with the product you used?

The best fertilizer for vegetable plants is a 2-1-2 NPK ratio. Extensive studies for many years have shown that food crops use nitrogen, phosphorus, and potassium in approximately that ratio.

Then, feeding small amounts on a weekly basis until about 3 weeks before harvest will assure a great yield of healthy vegetables. And continuing to feed your indeterminate tomatoes until 6-8 weeks before the first killing frost, will keep them producing at maximum capacity for many months.

Also, if you can find it, you will be well rewarded to include the secondary and micro nutrients in your fertilizer.

You can find a great formula that you can mix yourself at www.foodforeveryone.org. Look in the Gardening Techniques section under Fertilizers.

Jim

For most vegetables except the nitrogen loving ones a 1-2-1 ration of NPK is preferred. Tomatoes are especially fond of Phosphorous (Phosphate)so a 1-3-1 ratio should be fine.

With great respect for Farmerdill, I'll suggest that the reasons many people use the ratios Farmerdill proposes have some merit, and are three-fold. First, plants use most of the phosphorus they need in the first half of their growth cycle; second, phosphorus is not volatile, nor does it move very far in the soil, therefore applying it early is not wasting it; and third, most growers want to feed as few times as possible, and so will opt for only one or two feedings - then supplementing with nitrogen later on.

Dr. Mittleider's experience has taught us that small weekly feedings of a complete nutrient mix produces yields substantially greater than obtained using traditional methods, and so if you are going to follow traditional methods and only feed once or twice, a higher phosphate ratio is what you want, but we recommend regular small feedings in the ratio the nutrients are actually used by the plants over the course of their productive lives. :)

Jim Kennard

While we are fresh on the subject, I'd like to ask some of you very experienced tomato gardeners a question about fertilizer.

I was told before that you shouldn't fertilize your tomatoes until after the blossoms have formed. Is this true? I was told that if you fertilize before, you will end up with a big bushy plant, but few fruit.

Now, the person that told me this, uses steer manure, if that makes any difference.

I have limited space for my tomatoes, so I need to try my best to make sure each and every plant is very fruitful.

Not true.

Blossoms are forming from May into October. If you didn't fertilize until after they come on you would never fertilize.

I suspect the basis for this is the type of fertilizer used. A complete, balanced nutrient will keep your tomato plant healthy and growing productively until frost kills it. On the other hand, a fertilizer that is not balanced, but has too much nitrogen, in comparison with some of the other elements, will produce a plant with soft lush greenery, but little fruit.

Users of manure proudly proclaim that it only has 1-2% nitrogen, but they usually only apply it once - at the start of the season, and will often apply several inches to the entire planting area. In comparisons, I have found that very often nitrogen is over-applied early. This can actually burn the plant, and it sometimes gives the result you describe. But worst of all, because nitrogen is volatile, it is soon gone, the plant has none, and stops producing in about July, when it should just be getting up a good head of steam.

Using the balanced natural nutrients we recommend, and applying once each week, you give each plant only 5 hundredths of an ounce - less than 1/3 teaspoon! - of nitrogen each week (and similar amounts for the other macro's). That is never so much that it could harm the plant, but just keeps it growing and producing fruit vigorously throughout the season.

And there is never any harmful build-up of mineral salts - the way there can be with large amounts of manure applied all at once.

Feeding is all done very quickly, however, so don't be put off by the mental picture of standing in your garden with a teaspoon feeding each plant! You can see how to do it at www.foodforeveryone.org, in the Gardening Techniques section under Fertilizers.

Jim Kennard

Jim, Thank you.

And what do you think about using "kelp"? I have just learned about this and many gardeners say it's wonderful. I'd also like to know how often something like liquid kelp, diluted, should be applied.

What you said made alot of sense. I saved the link you gave me.

Jim,

guess not - that thread isn't leading me to anything! is it spelled wrong?

nevermind, hit the link you gave up earlier and that worked!

Coming in here late, I know, but whatever. LOL

I too subscribe to the 1:2:1 ratio for NPK.

Karrie, Contrary to what most folks read tomatoes are not heavy utilizers of fertilizer, particularly N.

I fertlize mine about two weeks after they're set out and then once more right beofore blossoms start opening and then not again unless the summer has been wet and I feel more is needed by judging what the plants look like.

But late in the season I would use a foliar spray of either seaweed (kelp) or fish emulsion since I can't get near enough to large plants, the way I grow them, to use anythng other than foliar sprays.

You asked about kelp before and I thought we had a nice discussion about it in that thread. I think seaweed (kelp) and fish emulsion sprays are a good idea in terms of providing micronutrients. But I usually do it only once per season, about one month after plants are in the ground, and then, as I said above, much later in the season if the season has been very wet.

I've been working with tomatoes since I was a kid back on the farm, and have seen all sorts of fertilizer regimens used. Later in life after I moved back east from the Med School in Denver and started growing more heirlooms, in a frenetic manner, LOL, I also worked very closely with the Cornell Cooperative Extension on a variety of projects.

They too suggest a 1:2:1 ratio for granular fertilizer or whatever.

But you are the one who has to find out what works best for you in terms of knowing what your soil has or doesn't have, and you might wish to have a soil test done, and you are the only one who experiences the weather in your area, so experiment.

The tomatoes will tell you when they aren't happy by a fading of the foliage which has nothing to do with a need for water. And most of the time the foliage fades it means they'd like some food. LOL Of course there are other reasons why foliage might fade, and actually folks who overuse triple phosphate know that well, and that's just one example, but almost always it means they need more nutrients.

So do try to experiment a bit and see what works for YOU. (smile)

Carolyn

Thanks to both of you! I actually DID test the soil last fall, and came to the conclusion that I won't be using one particular area again for tomatoes, but the side of the house, where my maters did do well, fared well in the tests I took (pH, NKP).

I think I will probably go ahead and use SOME (not alot) of fertilizers (be it kelp, steer manure or regular old store bought in the consistencies mentioned above) from start to finish, in small intervals and see what I come up with.

I will also add some compost to the soil this spring before planting anything, hoping that gives everything the boost it needs.

Carolyn, thanks for laying out an easy-to-follow feeding schedule. I've always done the "by guess and by gosh" method of vegetable plant fertilization - which sometimes works, and sometimes doesn't. (There'll probably always be a little of the haphazard/experimental approach to my gardening endeavours, but having someone clearly explain the when/why/what is great :)