Shop Products
Houzz Logo Print
daniel_ny

Watering my tomatoes

daniel_nyc
9 years ago

This year I decided to use drip irrigation. So, most of my tomatoes - except a few last minute additions - are watered from those emitters.

It works perfectly, the only problem is that I find it difficult to "guess", WHEN and FOR HOW LONG I should water the tomatoes ? People have different opinions regarding that "1 in. / week." I also find it pretty difficult to avoid the âÂÂuneven wateringâÂÂ. Some of my tomatoes are watery, so I'm sure I'm overwatering. Some cherry tomatoes split. I water less lately.

While I can check the soil humidity using a Soil Moisture Meter where my tomatoes have straw mulch, it's much more difficult to do that where I used fabric mulch. I'm VERY careful not to hurt tomatoes' roots, because in the past I had very, VERY bad experiences hurting unintentionally tomatoes roots. The tomatoes simply wilted in 2 days.

Even more difficult I find FERTILIZING using drip irrigation. Here are two threads I found in GardenWeb:

Fertilizing via drip irrigation and

Fertilizing with drip irrigation

Did anybody use EZ-FLO, Add-It fertilizer injector or Dosatron ?

Comments (37)

  • PupillaCharites
    9 years ago

    Daniel, I took a vacation and set up 10 days of a sort of drip watering for my tomatoes and thankfully nothing went wrong. When I got back I let it go a few more days just because it was a great rest, and during that time I saw the drawbacks of any system that isn't intelligent enough to limit overwatering.

    The problem is you set it up based on the conditions for the worst day (hot and dry) so the plants won't dry out and be hurt. Then you wake up the next day and it is raining, or the temperature is lower, or it is just very humid and moisture stays in the earth.

    Meanwhile your automatic watering goes merrily along dumping more water no matter what, and eventually you set up the conditions for disease in the roots like any chronic overwatering will lead to around my parts anyways. I have problems for the whole concept of drip watering tomatoes anyway since I subscribe to the good root watering to field capacity and letting the soil dry out a bit before the temporary wilt point, and that works better in my environment to control disease and the tomatoes seem to love it. YMMV.

    Based on that, I decided it wasn't worth it and I'm back to manually watering where I feed my tomato kids exactly what they need. It took me two weeks in advance to hone the flow rate on the irrigation system - more time than the vacation itself, and by the time I was back, both the plants were drinking a different amount and the weather had changed enough that a dumb system was getting to be like a fish out of water.

    I'm not sure what zone you are in, but these things will really vary. It says NY, but zone 10, which could be subtropical, or arid. I'm thinking in an arid hot area, drip irrigation might be very useful, but not in a spongy humid area.

    I mix all of my fertilizer by hand because I want to be darned sure what's going on so nothing suffers from salinity burn, and I have used a Dosatron type system, but not for this for that reason!

  • daniel_nyc
    Original Author
    9 years ago

    thank you PC for sharing your experience.

  • seysonn
    9 years ago

    You have to figure out, eg, how many inches of water/gallons is delivered. Say, a tomato plant's roots are spread under 4 sqr-ft of area.
    One inch of water/ rain will amount to about 2.5 gallons. That is about how much is needed per week, in ground, under landscape fabric. Lets say 3 gallons.

    The other thing is the soil's drainage quality. With a well drained soil a little more watering is not going to be crucial.

  • daniel_nyc
    Original Author
    9 years ago

    lehua13 wrote here:Drip irrigation with .5 gph drippers (GardenWeb)

    1" of water over a 2 foot diameter plant is 3.14 sf times 1/12 ft equals 0.26 cubic feet times 7.481 gallon/cf therefore is 1.9 gallons over three watering times is 0.6 gallons three time a week. It would take your 0.5 gph emitter watering the plants 2 hours per cycle. Your limiting factor is the pressure loss for each emitter. See if you can find the pressure loss per emitter on-line or let us know the brand and we can look it up for you. If the design pressure is around 25 psi the loss should be a certain psi. So you have 20 psi loss for the total loss of the zone.

    What do you think ?

  • daniel_nyc
    Original Author
    9 years ago

    NOBODY uses drip irrigation ??? That's pretty strange...

  • Jennie Sims
    9 years ago

    I use drip irrigation, but I grow in containers. Which is totally different in watering needs than in the ground. Have you tried the irrigation forum?

  • daniel_nyc
    Original Author
    8 years ago

    Last year,
    somebody – I don’t remember who – wrote that he does NOT water during the month
    of… August.

    I always
    mulch – both straw and landscaping fabric, both with their advantages and
    disadvantages – and I wanted to know your opinion, regarding not watering in
    the month of August.

    If no
    mulching, definitely watering is necessary – depending on the soil and the "jungle" 3-4 days in
    the 90s and the tomatoes will start wilting – but using fabric or even straw mulch, there is
    much less necessity to water.

    What do you think ?

  • Seysonn_ 8a-NC/HZ-7
    8 years ago

    daniel_nyc(7a)

    Last year,
    somebody – I don’t remember who – wrote that he does NOT water during the month
    of… August.

    ^^^^^^^^^^^^^^^^^

    Month of August is one of the 2 hottest months of summer !!! (July, August).

    Sey

  • Pumpkin (zone 10A)
    8 years ago

    I don't know who it was, but I'll admit to not really watering last August. However, that's the peak of the rainy season here and last Aug/Sept was exceptionally wet to the point that continuing to run my lawn sprinklers inadvertently gave my grapefruit tree foot rot. So, just depends on what August means at your house.

  • hp_MA6b
    8 years ago

    The person could be me. I haven't watered tomatoes AT ALL since May, At planting time in later April, I watered once and maybe a 2nd time a few days later.

    My garden is in Belmont, near Boston. I have practiced "no watering" for over 10 years.

    The benefits are obvious.All I need to do is to stake, spray, and pick.

    The taste of all types of tomatoes are excellent. Even my celebrity tastese really good too.

    Also I do not fertilize after planting. Only put lots of "good stuff" in planting hole and that's it.

    Right now the tomatoes are to my ears. We have given away to at least dozen friends.

  • hp_MA6b
    8 years ago

  • daniel_nyc
    Original Author
    8 years ago
    last modified: 8 years ago

    hp, I rotated your picture; hope it's ok with you.

    Nice jungle. How do you get inside that jungle ?

  • daniel_nyc
    Original Author
    8 years ago
    last modified: 8 years ago

    Last year, in the beginning I over-watered. The tomatoes were tasty but watery.

    After reading that post about not watering in August, I watered less, MUCH less, and the taste improved A LOT !

  • hp_MA6b
    8 years ago

    Thanks Daniel.

    Yay, it's a jungle. To borrow someone said, our garden is measured in inches. I put used wooden boards 8"~10" wide between every other tomato rows and walk on them. This way wouldn't compact the soil and roots can still grow under the boards.

  • rgreen48
    8 years ago

    I also cut back on watering in August. I should qualify that statement a bit... I actually try to cut back on watering while the fruits are blushing and ripening. It just so happens that for many tomatoes, that happens to be around the end of July through August.


    The 'downside' is that fruits still setting for a later harvest suffer a bit, but since blush time is usually also disease time, cutting back on water can help push back the problems caused by moisture.


    Here in Tn., it's also afternoon-storm season. We can get a storm every single afternoon during the heat of the summer. This year, July was like that... for 2 weeks straight, we had an afternoon or nighttime storm everyday for over 2 weeks. Cracking and watery fruits abounded. It also brought disease to the tomatoes, zucchini's and even winter squash. Oh well, you can control some factors, but not all of them.

  • Seysonn_ 8a-NC/HZ-7
    8 years ago

    If you don't water where do the foliage get moisture from, to grow under 85F++ sun ? Just a question.

    Sey

  • daniel_nyc
    Original Author
    8 years ago
    last modified: 8 years ago

    IMHO, with a good soil - and a nice root system - with a GOOD watering in the beginning of August + landscaping fabric mulch, I think not watering for 2 weeks wouldn't be a problem with 85' F.

    Now, 90'+ is a different story. I wouldn't guarantee for more than a week - or less. 95' F is NOT a joke. You can have the lowest during the night at 85' F, and that IS also a problem.

    Without mulching, and with the lower leaves / branches removed - so the soil is fully exposed to the sun - in 3-4 days of 95' F, imho, the plants will have problems. They might not wilt right away, but they will be stressed. And eventually, they WILL wilt.

    Now, if the plants have 3-4 ft. long roots, they might survive. The longest root I had was 2 ft. long. Plants get long roots, by watering infrequently but HEAVY. Watering little and often, will get short roots close to the surface, which will not be able to help when hot temperatures will dry the few inches of the soil's surface.
    JMO.

  • rgreen48
    8 years ago
    last modified: 8 years ago

    Mine must have pretty good roots. They're doing well. The early foliage was so thick, even with a lot of lower leaves taken off, the sun still doesn't reach my soil at all. I also don't remove as much spotted foliage as other growers. I started with a 6" - 8" layer of hay mulch, but that is down to almost nothing. I planted beans along the north side of the bed and they are shading about 1/3 of the 8' - 9' tall tomato plants.

    I did have to water one time during the late July dry spell we had. Surprisingly, it was the peppers which showed the first signs of water stress - probably shallower roots. I watered the peppers, eggplants, and tomatoes, but only enough to relieve the water stress.

    I learned long ago to recognize the first signs of water stress. This time of year BER isn't a problem. The plants will soon be dead, and new growth, while fruit is ripening, is not a plant priority. Am I sacrificing growth that may support later truss and fruit set? Perhaps, but it's a trade off. I prefer a more concentrated flavor over the relatively few fruits I might get before frost.

    If I wanted a later harvest, I would do a succession planting and water them diligently through July and August. However, my space, at the moment, is limited.

    The dry spell broke yesterday and we got one of our afternoon storms. Another front is coming through Tn. today and tomorrow. So, although hand watering is limited, nature gives what it will. As Daniel mentioned, a good early watering regimen, including very deep watering approx. once a week, will establish a root system well prepared to handle most dry spells.

  • daniel_nyc
    Original Author
    8 years ago

    So, how was your watering this month (August ?)

    Anybody, NO WATERING AT ALL ?

  • Seysonn_ 8a-NC/HZ-7
    8 years ago

    We never got enough rain even to wet the top 1/2' of soil. So I keep watering but less frequently ; like every 3rd or 4th day, depending on the temperatures.

    My raised beds are filled with well drain soil mix so they don't hold too much water.


    Sey

  • rgreen48
    8 years ago

    No watering here. We had some rain earlier in the month, but aside from heavy dews offering a nice amount of foliar moisture, it's been dry for about a week. Nothing is showing any water stress yet though.


    I have had to heavily defoliate the tomatoes in the last week or so, so the sun is hitting the mulch. In patches the mulch has completely decomposed and soil is peeking through. I've already taken in a good harvest, and one could argue it could always be better, but the freezer is full and I still have lots of peppers to soon put up.


    The tomatoes are setting fruit again, but hopefully they will ripen slowly enough to eat fresh.

  • daniel_nyc
    Original Author
    8 years ago
    last modified: 8 years ago

    rgreen48, post some recent pictures, please.

  • rgreen48
    8 years ago

    Keep in mind that I adhere to the Sergio Leone school of tomato growing...







  • rgreen48
    8 years ago




  • rgreen48
    8 years ago




    Yep, you'll find it all in this no-cides garden... The Good, The Bad, and The Ugly!


    At least the peppers are thriving... And as of today, those peppers are showing a little leaf droop. I'll probably water tomorrow morning. But, I don't know about anyone else, who ever heard of 6' tall pepper plants in one season! t's a first for me... maybe it's this southern climate; in NY I had, at best, maybe 4' tall peppers.



    The indeterminate tomatoes are about 9' or taller, just blown over and supported by the CRW cages. The peppers are just about as tall as those windblown maters. Crazy! Oh, and speaking of lessons learned... don't plant eggplant behind peppers, you may get a good year and your peppers will swollow the eggplants whole!

  • daniel_nyc
    Original Author
    8 years ago
    last modified: 8 years ago

    rgreen48, tx for posting the pictures.

    I LOVE PICTURES...

    Did you fertilize / fungicide ?

  • daniel_nyc
    Original Author
    8 years ago

    Question: How do you people know when to water your tomatoes ?

    1. I check the soil (with the finger)

    2. Tomatoes show signs that they need water (if yes, which signs ?)

    3. I have a watering schedule, which I respect no matter what.

    4. Other reasons (please specify)

  • rgreen48
    8 years ago
    last modified: 8 years ago

    Daniel, yw. Yes, I do use fertilizers. In this case, I fertilized at transplant, switched to an organic tomato specific fertilizer just before flowering, and one more light application at fruit set. I grow in a loamy clay, and except for being naturally low in N, fortunately the ground here is pretty fertile.

    I could have fertilized again, but my yields were fine enough for me, and I'm not one to spend resources without worthwhile returns. Same with water. I could be watering, and the day after those pics I went ahead and watered, but only just enough. Watering costs money and time. I already got my harvest, whatever more I get is above and beyond. I'll water again when absolutely necessary, but that's all.

    In fact, if we don't get the rain that they say may happen tomorrow or Monday, I'll need to water again in a day or 2.

    As for fungicides.. I use no 'cides at all. No fungicides, no herbicides, no insecticides. Just my fingers and whatever beneficial insects I can keep around. My plants are indeed ugly lol, but they serve my needs with plenty to spare.

    You ask when we know we need to water... I could go into detail, but I'll just say... it's an art based upon experiences; recommendations proven by experience; and knowing the cycles, needs of specific crops, and the signs and symptoms of those crops;... as well as knowing the ground in which they are planted.

    At this time of year, the tomatoes have already offered their main crop, but I still have peppers thriving. So, since peppers are generally more drought tolerant than tomatoes, and they handle neglect fairly well, I watch the pepper plants. When the peppers start to show signs of wilt (not actual stress, that will cause leaf-drop,) you know for sure that it's time to water the tomatoes.

    The finger test works fairly well early in the year, just gotta make sure you go deep enough. But at this time of year, the roots have been as deep as they were going to get for a while now, and I could care less if I get more top growth. Deep watering now is fine, and it will offer a reserve, but it's not as necessary. You'd have to be in a serious drought for the deep soil to dry out enough to warrant the same deep watering as earlier in the season that was beneficial to encourage a good root system.

    I might re-post with more specifics about knowing when to water, but I have a tendency to drone on... be gone with me!...

  • daniel_nyc
    Original Author
    8 years ago
    last modified: 8 years ago

    Thank you rgreen48, interesting info. And please post more specifics about knowing when to water.
    Question: What do you think about the following statements:

    > "Give Them An Inch. Like most other vegetables in the garden, tomatoes need at least one inch of rain or irrigation water per week for steady growth." (Garden.org)

    > "As a rule, tomato plants require 1 to 2 inches of water a week." (SF Gate – Home Guides)

    Do you think that 1 - or even 2 – inches of water weekly are enough ?
    Imo, 1 in. of water – depending in the soil - can penetrate the soil 1-2 in. deep, which I think it's NOT enough to feed tomatoes’ roots (which are much deeper than that.)

    2 in. of water might go 2-3 in. deep, which again, imo, is not enough.

    What do you think ?

    Oh my! An inch of rain is 4.7 Gallons, AND 5.6 too!

    Watering volume per planting (rather than by 'inches')

  • Seysonn_ 8a-NC/HZ-7
    8 years ago

    INCHES OF WATER:

    One gallon = 231 cu. inch.

    One inch of rain = 0.62 gallon per sqr-ft. Two inches of rain = 1.25 gal/ sqr-ft.

    If a tomato root is under 3 sqr-ft , ONE inch of water ( Rain) is equivalent to 1.9 gallons of water per plant OR 2 inches is equivalent to 3.8 gallons. IMO, that is quite enough for each round of watering

    Another point is that how moisture retentive soil is and how dry it has gotten before watering.

    FINAL NOTE: I water roughly equivalent to ONE inch of rain. And it works fine for me.

    .I wonder how much a drip system provides per sqr-ft !!!

    Sey

  • daniel_nyc
    Original Author
    8 years ago
    last modified: 8 years ago

    Sey wrote:

    > I water roughly equivalent to ONE inch of rain. And it works fine for me.

    It might work fine for you because your plants are pretty close to each other.

    Planting tomatoes at 3 ft. between them - as many places recommend - things would be very different, imo.

    Anyway, my question is: 1 in. of water penetrate HOW DEEP in the soil ?

    Tomatoes' roots can be anywhere from 4 in. to 20 in. or more, long / deep.

    Is that 1 in. of water enough to feed those roots ?

  • Seysonn_ 8a-NC/HZ-7
    8 years ago

    Daniel wrote:

    >>Anyway, my question is: 1 in. of water penetrate HOW DEEP in the soil ? <<<

    ^^^^^^^^^^^^^

    Well is depends :

    ---(1) Moisture retention of the soil.

    --- (2) Condition of the soil before watering : that is, how moist was it ?

    EXAMPLE:

    (1)Take a column of soil, one square inch in cross section.

    (2) add one cubic inch of water ( 0.56 oz) to it from top.

    (3) Observe how far down it will penetrate.

    In the absence of an experiment, I think it will go down more than 12" in my garden soil.

    ANOTHER EXAMPLE:

    Take a 3.5" x 3.5" pot, 4" tall (seedling pot).

    it has 12.25 square inches surface area. If you give it one inch of water it will be about 7 oz of water. THAT IS A LOT OF WATER. Two oz will be enough to see water coming out of the drain holes. Now if it was 12" tall, still 7 oz would be too much. THAT IS EQUIVALENT TO WATERING YOUR GARDEN ONE INCH.

    Again, it all would depend on the moisture level in the soil prior to watering AND moisture retentiveness of a given soil : sandy ? clay ? loamy ? amount of organic matter ?

    Sey

  • daniel_nyc
    Original Author
    8 years ago

    Tx Sey.

    I was wondering which are the symptoms of over-watering ?

    On the branches, fruits...

  • digdirt2
    8 years ago

    As Seysonn and others said it begins with first understanding your soil, its composition and how well it drains or retains water. Have you heard of the Mason Jar Soil test?


    http://www.ext.colostate.edu/mg/gardennotes/214.html

    Not perfect but a good place to start toward that soil understanding and how to fix/improve it.

    Then you can do a perk test on your soil to determine how quickly it drains, how quickly water will permeate it (or won't.


    http://www.todayshomeowner.com/diy-soil-drainage-perk-test-for-your-yard/

    That gives you a good indicator for how long to water to get the depth of moisture your plants need.

    Symptoms of overwatering in tomato plants: lime green-yellow older leaves, leaf roll (taco shell roll), nutrient deficiency symptoms, root rot, watery tasting fruit, splitting fruit, stunted plant growth, etc.

    Dave

  • daniel_nyc
    Original Author
    8 years ago

    Thank you Dave.

    Now, what are the symptoms of under-watering ?

  • Seysonn_ 8a-NC/HZ-7
    8 years ago

    the symptoms of under-watering ?

    It is wilting and shedding lower leaves.

    Sey

  • daniel_nyc
    Original Author
    8 years ago

    Those are the LAST symptoms.

    Before that...?

Sponsored
Winks Remodeling & Handyman Services
Average rating: 5 out of 5 stars1 Review
Custom Craftsmanship & Construction Solutions in Franklin County