It’s May at last and at the end of this month, plants can stay outdoors – frost free. Before they reach their final home, it’s worth considering how we are going to water and feed tomatoes in containers.

Some of my plants are desperate to be potted on, so the final large container will be very welcome.

How To Water and Feed Tomatoes in Containers

Planning for watering and feeding
Air pots need an additional wick of capillary matting added if they are watered from below in trays (think holiday).

How To Water and Feed Tomatoes in Containers

Standard large pots that are deep (more than 9 inches) would do better with an air pipe. Also, if a pot or container is very tall it’s best to water it from above (from time to time) owing to the limits of capillary action. An alternative is to use a capillary wick.

All growing media is better with perlite added – roots need oxygen and so do soil microbes (bacteria and fungi are very important for organic growing).

Feeding in containers

The chemical nutrient approach
Using the nutrients already available in the new soil, be it a grow bag or multi-purpose compost, then on to a Tomorite type feed when plants begin to flower and fruit.

This is probably the most popular way to feed tomato plants but it’s a bit hit and miss, depending on all sorts of growing conditions.

Bio Nutrients
New soil with extra organic feed added, such as fish, blood and bone – only 75p at wilko’s, then organics for flowering and fruiting.

The challenge here is to find organic nutrients that promote flowering and fruiting – high in potash. There are products on the market for feeding plants that are fruiting such as:

Tomato taste and nutrients
Last season, the weather was very good compared to the previous five or six seasons, and many gardeners in the UK had a huge crop of tomatoes.

The one area in which I was disappointed was the taste of some varieties.

Of course my home grown tomatoes always taste better than shop bought toms, but the quest for excellence should also include learning ways to maximise the natural flavour of each variety – quality as well as quantity.

This is where the chemical versus the bio approach is relevant.

Over feeding some mineral salts, namely nitrogen and some of the trace elements (when using chemical feeds) can reduce the flavour of tomatoes.

The beauty of the organic approach is that it is led by soil microbes. It is they who turn organic matter into plant food, and importantly, at a rate that is best for plant growth and tomato taste.

So why should organic tomatoes taste better than those fed with chemical based nutrients? This is a controversial subject!

Because plants receive the nutrients that friendly bacteria have made and not the ones that where made at the chemical factory!

It’s about balance and strength
Plant roots in conjunction with soil microbes form a relationship in organic growing that produces the right balance and strength of nutrients for the plant. This makes it difficult to over feed and to give the wrong balance of nutrients.

It is both the wrong nutrient strength and nutrient balance that reduced the flavour of my toms last season – although I did have an amazing amount of tomatoes!

This season I’m testing a number of organic options and comparing them with the traditional “new compost then tomorite” approach.

I expect both methods to produce plenty of tomatoes but ultimately –  it’s the taste that counts.

It is much easier to feed the right amount of nutrients using organic methods because the friendly microbes in the soil are involved.

It’s always good to know what you think … please leave a comment below if you would like to!



Plants still need to be kept under cover at night – until the end of May in the UK to protect them from frost.

Watering in the morning is best so that plants won’t sit in wet cold soil overnight.

One of the best supplementary feeds is liquid seaweed. It can be used as a foliar spray and plants love it!






7 Responses

  1. terry scoates
    | Reply

    Hi Nick, please can you give me some advice, This morning I went to pot some Tomato plants into final pots, I got as far as filling the pots half way with compost and Vermiculite when I noticed the compost in the pots were full of Ants and so was the rest of the Compost in the bag.
    I have put some Ant Powder into the pots and the compost bag, If I plant the Tomato plants now into the pots will they be ok or will the Ant Powder kill the plants or should I start again?.
    best regards from terry

    • Nick
      | Reply

      Hi Terry,
      To be honest I don’t know but to be on the safe side I would start again.

  2. Helen
    | Reply

    Hi Nick
    We have had some very unseasonal rain
    Very heavy and very prolonged over night
    Unfortunately I couldnt get out to protect them
    I know you have mentioned that Tomatoes dont like rain
    What is the best thing to do now?

    • Nick
      | Reply

      Hi Helen,
      They’ll be ok with just one day of rain. Let the soil dry out a bit and put them in a light airy place if they are in containers.
      The combination of wet cold leaves in saturated soil is the danger.

  3. ray
    | Reply

    I personally believe it does not matter if the plants are fed organically or chemically, the taste is still the same, the plant dos’nt know if it gets it food from a tin or not.

  4. Milly Thompson
    | Reply

    Hello. The yellow plastic wick gadget you’ve pictured in today’s newsletter.
    Where can you buy one? I’ve looked everywhere.

    • Nick
      | Reply

      Hi Milly,
      The wick is the green strip of capillary matting and the yellow base is the bottom of the air pot. I just buy a few metres of capillary matting and it does a lot of useful jobs.

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