Whats Wrong With These Plants?

[Walt B.]

I'm trying to figure out why one of my tomato boxes is struggling a bit. I have two 7'x4' SIPs filled with Raybo's 3-2-1 mix. One of my boxes with 2 cherry tomatoes looks fine....no wilt or leaf discoloration......the other box with 6 plants looks stressed. Some leaf curling and purplish veins on the underside of the leaves. I mixed in Tomato-Tone initially and have been top water fertilizing with Texas Tomato Food weekly for the last two weeks (seeds started in late January....planted on 3/21). The weather has been pleasant all spring (high 70's) . I'm leaning towards phosphorous deficiency but would like to hear more seasoned opinions.

[Walt B.]

We have had a couple of cooler nights in a row.........mid 40's. Maybe has something to do with it. Except the cherry tomatoes show no similar symptoms and neither does the tomatoes in the ground for that matter.

[edweather]

Sounds like your mix is good. Just curious why you used Tomato Tone in an SIP. From what I've read organics have a hard time breaking down in a soil less mix due to lack of microbes, and are better suited for in ground applications. Not quite sure why you are top fertilizing, but probably can't due much harm. When I had my SIP's I would only fertilize through the water I filled them with. Actually I would feed them every time I filled the reservoir with a weak fertilizer solution. The Texas food should work well for that. How often are you adding water?

[Walt B.]

Tomato Tone does include the microbes that break down the fertilizer.....and secondly its recommended by Raybo who's mix I'm using. I'm new to Texas Tomato Food fertilizer and weak as it is.....I'm wary of overfertilizing by mixing it directly into the reservoirs of my SIPS which hold about 55 gallons of water. At least until I get more familiar with this particular fertilizer. I'm filling the reservoir about every 15 days but the reservoir is dry before that.

[edweather]

[QUOTE=Walt B.;640286]Tomato Tone does include the microbes that break down the fertilizer.....and secondly its recommended by Raybo who's mix I'm using. QUOTE]

OK, sorry, I didn't realize that. Are there tomatoes on the plants yet? I know my smaller plants and seedlings commonly have purple undersides that go away over time. Purple undersides usually indicate lack of P, but it seems there should be plenty available. Did you use the recommended amount of lime in the mix? I agree the leaves look a little stressed, but not too bad. Maybe cool nights are the issue. It might correct over time.

[Cole_Robbie]

Those microbes are highly dependent upon temperature. It has to be warm before they can thrive, or at least not too cold. It's the same with any organic fertilizer. I think you'll be fine when it warms up.

[Walt B.]

I checked the PH before I planted and it was 7ish....but that was with one of those cheap PH testers so who knows how accurate that reading is. I did inoculate the roots with mycorrhizal fungi on planting out. It certainly has been brisk at night the last week or so (mid 40's).....so that could certainly be a factor. But considering the tomatoes in the other box (cherry tomatoes) and the ones planted in the ground don't seem to be affected I'm not so sure.

There are quite a few tomatoes on the plants already......some golf ball sized already. I do worry about overwatering......and I'm not refilling the reservoir as fast as I did last year allowing things to dry out a bit, but by design you shouldn't be able to overwater these SIPs as the wicking properties are more dependent on the amount of soil media that is in contact with the reservoir (between the landscape piping) and not the amount of water in the reservoir.

[RayR]

Originally Posted by Cole_Robbie

Those microbes are highly dependent upon temperature. It has to be warm before they can thrive, or at least not too cold. It's the same with any organic fertilizer. I think you'll be fine when it warms up.

Looking at the Sacramento weather forecast, the temps haven't been that bad. warm daytime temperatures and 50's at night. Warmer than here with daytime swings from high 40's to 70 sometimes and nights in the 40's most of the time. My plants are still potted up and I take them outside in the day if there's no storms or high winds and usually bring them in the garage for the night. All mine are feed organically and inoculated and have not a stitch of any sign of nutrient deficiency. So I'm not thinking Walt's problem is temperature related. I've not seen P deficiency myself in the past unless the soil temp was real cold, like 30's or low 40's.
Sure, microbial activity is related to temperature but he's also using nutrient salts from the TTF which are not dependent on microbial activity.

[RayR]

It does look like P deficiency, the question is why? P deficiency is typically caused by either cold soils, a real lack of available phosphorus, overly wet soil (lack of oxygen in the root zone), or a soil water PH issue (too low or too high a PH will limit P uptake)
Walt's fertilizer regimen is a mix of organic and conventional. Tomato-Tone mixed into the soil is fine, it contains some beneficial bacteria to help to mineralize nutrients (I would prefer to have the roots inoculated with mycorrhizal fungi when they were small transplants to provide the plants with more soluble P).
Even so, the Texas Tomato Food supplies available P directly to the roots, so P availability really shouldn't be a problem.
I'm guessing the soil conditions are too wet or there is a PH issue. ?????

[oakley]

Have you had any strong winds with cool nights? I've got some of that going on and i'm
a bit concerned. We've had some cool nights. High winds yesterday. The trays under a
folding table were more protected and seem fine. A couple trays that were left out on
top got a bit beat up. They also received some unexpected morning sun as the sun's
path changed quicker than i expected. Noticed that Sunday being home all day.