Homegrown Tomatoes

Posts Tagged ‘tomato fertilizers’

The Great Tomato Experiment is underway!  This is the first report of the series, and the race is just beginning.

While you can read the full story behind The Great Tomato Experiment, a summary is as follows:

There are three plants, grown from seed from the same packet (plant variety is the heirloom tomato Pineapple). 

• One plant is the control plant; it gets treated the same was as my other (non-experiment) tomatoes.
• Another plant is being grown for fruit size, per the book Giant Tomatoes.
• The third plant is being grown for productivity of harvest, per the book How to Grow World Record Tomatoes.

All three tomatoes were planted in 10-gallon containers.  Because they are planted in containers, they get fed weekly, although about half strength.

(Note:  You can click on each of the photos to see a larger version.)

Fruit Size Plant

The first plant is the one I am growing for the size of the fruit.  This plant’s soil is about half and half compost and potting mix.  Fertilizer has been mainly Miracle Gro for Tomatoes (half strength), as well as some kelp spray and a little bit of fish emulsion.  Oh, and I did also add some worm castings.

This plant is by far the largest of the three, as far as height goes.  It’s also a little bit leggier, which I suspect is from the Miracle Gro’s higher nutrient count.  Because it’s in a container, the plant gets a little Miracle Gro liquid every week, at half strength.  It also gets some kelp liquid once a week.

The first blossom buds appeared on this plant, just this past week.  But per the book, I pinched them off — the plant needs to grow some more before setting the first fruits.  (Oh boy, was it ever hard to pinch those blossoms off!)

Harvest Size Plant

This plant has been lagging behind, but now it’s starting to catch up some.  The mix in the container was 100% compost.  I also added worm castings, bone meal and blood meal.  The plant gets fish emulsion spray once a week, and now that it’s large enough, also a drink of some (slightly diluted) fish emulsion weekly.  It also got some kelp meal, and a once-a-week spray of kelp liquid (“Sea Magic”).

This plant is the stockiest of the three plants, even though it’s shortest in height.  The theory behing this is that while plants grown 100% organically take longer to “take off” as far as height, they grow better and healthier once they do start to catch up. 

And you know what was interesting?  When I walked out to the garden at lunch, this plant was noticeably larger/taller than in the photo (taken yesterday morning).  The top leaves now drape over the green bar!

Control Plant

The control plant is growing along nicely so far.  It’s planting mix was about 70% compost and 30% potting soil. 

As far as fertilizer, it’s been mostly organic — worm castings, fish emulsion, kelp meal and spray.  I have also added some Tomatoes Alive! all-natural fertilizer.  I also gave the plant a shot of Miracle Gro for Tomatoes (diluted to half-strength) about a week after I planted it .  The reason I did this is because I saw the underside of the leaves had some purple veining — a good hint that the plant didn’t have enough phosphorus.  It’s doing fine now, though, without any extra Miracle Gro.

As far as height and stockiness goes, it’s somewhere between the fruit size and fruit production plants on both counts.  So likely I’ll quit using the Miracle Gro, and concentrate on organic methods from this point out with this plant.

When’s the Next Report?

I figure about every two weeks is a good time period between reports.  So look for my next one on The Great Tomato Experiment around the end of March.  Can’t wait to compare photos then!

Now that you know what makes up fertilizer, the next question might be how to actually use the fertilizer on your tomato plants.  Even tomatoes grown organically in rich soil need some help in times of swift growth or when having lots of fruit on the plant.

There are several ways to apply the fertilizer:  foliar, liquid and granular.  Each has its strengths and weaknesses, which is what I’ll discuss in this post.  And in actuality, you may choose two or all three methods at different points in your tomato plant’s life.

Foliar Fertilizer

Foliar fertilizer is sprayed onto your tomato plants and absorbed through the leaves.   The absorption rate is swift, and many growers (including me) swear by foliar fertilizing for healthy tomato plants.

Foliar fertilizers in general should be diluted, so that there is no chance of the plant’s leaves being burned.  Good bets for organic foliar fertilizers include Terracycle, liquid seaweed and fish emulsion.

The downside for this fertilizing method is that it must be done early in the morning, before the dew dries.  This is because that’s when the plant’s stoma are open and receptive.  Later on in the day, the stoma are closed, so even if you did a foliar feeding, it wouldn’t be absorbed.

Some people say you can also foliar feed in the evening, when the stoma are once again open.  However, I don’t like to leave my tomato leaves damp in the evening because I feel it increases the risk of fungal diseases in my humid climate.

Liquid Fertilizer

Liquid fertilizer is pretty much what it sounds like; a fertilizer diluted in water.  Liquids can be used both for foliar feedings as well as drenches (i.e. pouring on the soil around the plants).

If you choose to use the liquid fertilizer as a foliar feeding, dilute to 1/2 the strength suggested on the instructions.  If you choose to use it as a drench, give the plants a light watering before applying the drench.

When using a drench, make sure you aren’t splashing any soil up onto the tomato stems or leaves, to reduce the risk of any soil bacteria that may be present  from getting on the plants.

Granular Fertilizer

Granular fertilizer is in solid form and generally sprinkled on top of the soil around the tomato plant.  Some granular fertilizers can be mixed into the soil before you transplant into your garden or a container.

Granular fertilizers can be time-released, feeding the plant over the course of several months.  However, I don’t generally recommend that because the needs of the tomato plant change as the plant gets larger and starts to bear fruit.  I feel that a granular fertilizer that is good for one month is more appropriate…unless it is a granular fertilizer made specifically for tomatoes, like Tomatoes Alive!® Plus 100% All-Natural Fertilizer.

I’m also including solid fertilizers like Jobe’s Tomato Boomers in this category, because they function roughly the same as granular.

Don’t Over Fertilize

The most common mistake is over fertilizing the tomato plants.  I know, it’s tempting to want the plants to grow big right away, but using a lot of fertilizer isn’t the way to get strong, healthy plants.  A lighter touch yields better results.

The exception is if you are growing your tomato plants in containers.  Since you need to water them more often, you’ll also need to fertilize them more often.  It’s better to use less than you think you need at first, because you can always add more.  But if you use too much fertilizer at one time, you risk burning the roots (not a good thing).