Supplemental fertilizer

[SueCT]

In a garden with lots of compost and well composted manure, would or do you still fertilize with commercial fertilizers, organic or otherwise?

[RayR]

Sue, fertility is something that has to be taken on a case by case basis. Read your tomato leaves, if the plants are thriving, growing and blooming then don't mess with it. Avoid the temptation to over fertilize, more is not usually better, it's more often worse.
If you see a problem, then post some pictures. Somebody will likely recognize the issue and recommend a correction. We all learn from each other's problems.

[Gardeneer]

Try to learn lips reading of your plants.
Of the 3 NPK, P and K are pretty stable. In an established garden there should enough of them already. What s often lacking is N. But if your soil is rich in organic matter it should retain N for longer time.
Having said that I supplement during the season with water soluble fertilizers at 1/4 to 1/3 regular strength every 2 weeks or so. This way I can be sure that I have not overdone it and then wait and listen to my plants. I don't like pushing my plants, as they do in commercial greenhouses. JMO

[zipcode]

Manure is a fertilizer. You don't need anything else as long as micronutrients are there (true for most soils). I find cow manure best for tomatoes from the commonly available ones (much better than chicken). Just add some regularly and that's enough if you don't cultivate intensely, in which case some minerals will get depleted in time.

[bower]

Growing in containers, I usually see the first sign of deficiency when the first fruits are starting to ripen. Yellowing lower leaves, as the plant scavenges nitrogen from the old foliage. In that situation, I found they could be kept healthy and green by giving them some extra ferts.

[digsdirt]

n a garden with lots of compost and well composted manure, would or do you still fertilize with commercial fertilizers, organic or otherwise?

I agree with Ray that it is a case by case issue. Primarily because I have found that "lots of compost" is a subjective judgement - what is 'lots' and 'compost' to one person is often 'very little' and 'junk stuff' to me and others.

And because compost, even really good stuff, alone isn't enough. You also have to have the well-developed and active soil residents to make it work. Developing that herd and keeping them well fed and active takes time and depends on the climate/weather.

So a qualified answer to your question - IF one's garden soil has at least 30% quality organic matter content and IF one regularly supplements that organic matter with an additional 4-6" at least 2x a season and IF there are clear signs of bacterial and fungal decomp and IF there are ample natural recyclers (worms, pill bugs, ants, etc.) present in any soil sample THEN, no additional supplements are needed. Otherwise additional supplements in small but regular doses will be a benefit for the plants.

IME as a soil consultant those ideal circumstances I outlined above rarely exist. The gardener just 'thinks' they do because of the effort he/she has made in the past. And they can't understand why the plants show the symptoms of insufficiency. So I encourage them to provide additional organic supplements while doubling their efforts at improving their soil and doing it consistently.

Dave

[Cole_Robbie]

I second the cow manure endorsement. Cow field topsoil is what I use for the garden beds.

Container plants grown in a pro mix get a light feeding of the tomato Miracle Grow about every other watering.

[b54red]

As someone who has added tons and tons of manure to his garden over the years and tons of compost I will disagree with most everyone else. I did fairly well with all the compost and manure as well as other good soil amendments but when I started giving my plants a soluble or liquid fertilizer feeding every week to ten days my production more than doubled in most cases and my plants just looked healthier and lived longer.

Before I started doing this my plants would have a definite lull sometime before the first fruits would be ripe and fruit set would drop to nearly nothing after the first few trusses ripened. So I started giving them a little supplemental feeding about every month to six weeks and things improved but I still had big lapses in fruit set and in production. So I experimented with a weekly feeding with dilute Miracle Grow on just a few of my plants to see what would happen and things started looking up; but it wasn't until I started the nearly weekly feedings with Texas Tomato Food that things really took off. I now plant far fewer total plants during a season yet my production has shown a huge increase and overall fruit size has been larger too.

Now this may not apply to your climate and garden because I live in an area where the season is extremely long at the least 7 months long and sometimes up to 10 months long. The climate here is very hot and humid for most of the season and foliage diseases take a huge toll on plants during that long season so leaves must be constantly replaced. We also get frequent very heavy rains that leach nutrients out of the soil and the plants suffer from that; but even during very dry months the supplemental feeding seems to give the plants a boost especially with fruit set.

Bill

[bower]

Originally Posted by digsdirt

I agree with Ray that it is a case by case issue. Primarily because I have found that "lots of compost" is a subjective judgement - what is 'lots' and 'compost' to one person is often 'very little' and 'junk stuff' to me and others.

Dave

Speaking of junk compost, I used some pretty poor stuff this year which contains a lot of coarse material mainly herb straw that isn't broken down and seems to be tying up nitrogen which the plants need now that they're setting a lot. What I'm noticing is that the fruit are not sizing up at a normal rate, although the overall fruit set is good.
I have been compensating with extra feeding - some pelleted slow release chicken manure 5-3-2, and also some fish emulsion/blackstrap liquid fert. I recently picked up some 'bone and blood meal' product (7-5-0 with 4 % calcium and 50% organic matter) which I'm thinking to try as a top dressing and cover with some actually decent compost. They recommend 40 g (5 tablespoons) per square meter for vegetables; so I am wondering, is this amount adequate to the specific case, or do you think I should bump it up a bit?

[SueCT]

Some history of my garden here. I used to apply compost every couple years in my veggie garden and my plants did quite well. The garden was on a hill and the ones at the top started to do poorly, and I was not sure if it was water issues from the hill and too much water rolling downhill and not getting absorbed and making it to the plants roots, or a nutrient problem, so I got a soil test. My first one. They said I had "too much organic matter" and/or over fertilized because all nutrients were also too high. I was admittedly skeptical but had read and been told so many times how important it was to get a soil test, I went with it. I brought in top soil to mix in and lower my too high organic content. Guess what? WORST Tomato year ever! So this year I brought more back in, A yard of half compost and half well composted cow manure. I have NO plans to get another soil test unless it is to test the pH to make sure the nutrients are available to the plants. I rarely fertilized, at most 1-2 applications of Miracle Grow or fish emulsion or one of tomato tone per year. Have to say can't remember using fertilizer more than once a year in several years, and several years none at all. I am talking about over the last 10 years now. As I added more compost every couple years I cut back more and more on fertilizer. It fits right in with that lazy gene I inherited. Later tonight I will flip through my garden journal that I have had for the past 8 years and see how many entries I can find that I fertilized.

Since I have brought in the the top soil and now more compost and manure, the bed has leveled off a lot, and is almost flat now, so watering should not be a problem.

Before anyone asks, I live alone and can't come close to producing enough organic waste to create as much compost as I need, so I do buy it. The current batch comes from a local farm and has been used with great success by family members in the past.

I was planning NOT to fertilize and just watch and see if they seem to need it. But then I was second guessing myself and wondered it was better to try to prevent them from developing problems in the first place. I think I read that some people do fertilize on a schedule and not just a reaction to problems or symptoms.

I think now it would be better if I didn't. I won't really know how much the compost and manure helped unless I wait and see how it does before doing something else.