[tomato] tomato techniques
Poris (Tomato@GlobalGarden.com)
Fri, 15 May 1998 13:06:06 EDT
>Replying to the threads about ebb and flow vs. other techniques.<
Here are some of my observations after doing much experimentation with
different methods of outdoor hydroponic tomato cultivation over the last 23
years (wow I must be getting old). My formulation has been virtually
identical over the years (I make it up myself). I have grown these in the
hills south of San Francisco (about 1000’ above sea level) and within 200
yards of the pacific ocean (northern Monterey Bay).
My first attempts used ebb and flow in 7" deep red lava gravel with only 6
hours of direct sunlight. Sweet 100’s grew to 12 feet and lasted from June to
January, I was hooked!! I switched from lava rock to 3/8" river gravel
(easier to clean) after a year or two. No observed differences between the
mediums. Years later at the beach another system used 5 gallon white food
grade buckets (1 or 2 plants per bucket) with about 12" of gravel (and some
with 6" of styrafoam on the bottom, I was trying to use up this unrecyclable
stuff) connected up with ½ " PVC. I had these all over the yard and on the
roof facing the ocean (southerly). I did not get better, faster or tastier
tomatoes from providing more room for the roots. The technique allowed me to
use the available space more efficiently, minimize the amount of gravel and
the size of the nutrient tank though. The biggest change was due to the
environment of the beach (more fog, lower daily temperatures, higher average
relative humidity and slightly more wind than the hills). Because of the
weight associated with the gravel and reading about NFT and other newer
techniques, I then tried my current method of 20’ long tilted beds with 3/8"
pea gravel 14" wide or so and a few inches deep. I tend to water more
frequently for a shorter period of time with this method. Comparable results
to ebb and flow, but the roots tended to stay in the bottom half of the bed.
At the end of the season, the whole bed was a continuous mat of roots. Next I
switched to perlite (I thought I would get more wicking of the solution to the
top half of the medium). I did get more roots, growth throughout the bottom
90% of the medium. The first year (1997) was slightly less successful than
the previous year (my guess is seedling quality), but this year it is doing
better than average (based on seedling quality and growth rate only at this
date). By the way, what would you call this technique?
My general observations are:
-the health of the seedling (at about 8 weeks from seed) is very important to
future performance (obviously). I usually grow 2 plants of the same species
and have qualitatively observed this to be true, the stronger seedling
outperformed the weaker seedling most of the time (I often had variations in
direct sunlight exposure time between plants that proved to be more
significant). The technique used to grow the seedling is also very important,
this is an area that I am still improving.
-the environmental conditions over the entire growing season are a very big
variable (even in my experiments where the conditions from April to November
are extremely uniform year to year compared to a large fraction of the US).
-If given adequate space and nutrients, the tomatoes will achieve a very large
fraction of their potential to produce high quality and quantity of fruit.
This does not mean that another 20% or more yield could not be achieved by
improved techniques, but for the hobbyist this is a satisfying result.
Quantifying quality is very difficult, my statements regarding quality must be
taken with a grain of salt (hydroponic food) since they rely on memory over a
period of years. They also are based on poor experimental technique because of
the inability to define all of the variables at one time (it is hard to
control the weather!). For me and my experiments, it is almost always
related to the length of direct sunlight (it has been from 4 hours to 7 hours
a day) and the day and the night temperatures early in the season. What is
the limit on how close you can pack the plants, how little nutrients you can
provide, how "uncomfortable" you can make the root system (pH, conductivity,
oxygen,…) and how lousy the weather can be is not in my immediate plans.
-the genetics of the plants are also very important. I have had some
difficulty growing late "beefsteak" type tomatoes in my environments mostly
due to low night temperatures (in the high 40’s through June) and limited
daytime sun exposure. I may only get 5 pounds from a plant and 2 pounds of
them are excellent quality, but I still grow them. I still grow some hybrids
because whoever engineered them made some decisions that coincide with what I
am looking for in a tomato. You can’t beat Early Girl for a medium size
tomato based on healthiness, yield, uniformity, reproducibility from year to
year and flavor. Sweet 100 and Sun Gold are also some of my favorite hybrids
for various reasons. Most of my experiments with "cooking" tomatoes have been
unsuccessful in finding ones with acceptable flavor. Currently I grow Amish
Paste and am extremely happy with it. Although not defined as a cooking
tomato, Costaluto Genovese has less gelatin and more pulp than most medium to
large tomatoes making it a good choice for sauce or salsa. Try lots of
different species (especially heirlooms), your local environment is not common
to everyone, you may get different results from others. Large variations in
yield and quality can be experienced in the same system.
Jaime (in the Santa Cruz Mountains in Northern California)