Tomato Plant Leaves Turning Yellow (From What?)

[jh43nm]

Hi everyone,

One group (in pots) of my tomatoe plants are turing yellow at the bottom on the leaves. I usually water them 2 times in the day because it can be quite dry here in Perth Australia. But from reading the boards it seems like over watering may be the cause.

I also add dynamic lifter, both organic and that for tomatoes, lime, epson salts and vacuum cleaning fluff (Heard from a video that it was high in magnesium) to them when I feel like it.

Most of my crop of tomatoes are in pots and are slowly turing yellow at the bottom leaves, but other than that they seem moderatley happy.

Any advice or comments would be most helpful and apriciated. [/img]

[TZ -OH6]

Yellow lower leaves are often due to nutrient limitation. The plant is pulling nutrients, mostly nitrogen, out of the old leaves in order to grow new leaves. If the plant is over watered the roots may be damaged and cannot pull enough nutrients from the soil. Do your plants wilt daily from lack of water? Do you stick your finger deep down to check moisture levels?


If you are confident that your watering practices are not creating a root suffocating bucket of mud, then I would try a little light fertilizing with a liquid fertilizer. Tomato plants in the gound have extensive root systems that continue to spread all summer and pull nutrients from a lot of soil, but in a bucket/pot they just do not have that much soil volume available, fill it with roots quickly and can use what nutrients are there quickly in a feast/famine cycle.

[jh43nm]

The plants don't wilt usually but it makes sense that they would be struggling as I have about 4 plants growing in the same pot. I wouldn't say that they are sitting in mud but I've decided to water them in the bottom of the pot where I have a tray.

Does this mean I should give them more fertiliser or less?

I'll try giving one group some liquid fertiliser and the other group none. Most plants have at least 15 green tomatoes from 1/4 to 3/4size.

[TZ -OH6]

Bottom watering only may not allow moisture to wick up to the upper level of the pot, and thus decrease effective size of the pot. Without moisture the roots cannot get nutrients, and without more or less constant moisture, the root hairs die decreasing the function of the roots when moisture is there.


Four plants per pot? How big are the pots? What varieties of tomatoes are they. You definitely have root competition for moisture and nutrients going on there, and probably light competition as well because each plant will partially shade the others. This will affect fruit production/quality.

[jh43nm]

Thanks for your help, the leaf issue is slowing down. I began to water less from the top and gave them some liquid fertiliser.