Kitchen Garden Forum

I'm new to the forum and joined to ask about watering tomatoes - although i hope to enjoy the general chat also. So, i've been reasonably succesful with greenhouse tomatoes in a border but i've never got to grips with how much to water. Advice i've read varies between watering everyday to twice or three times a week but it doesn't say 2 litres per plant for example. It seems the weather plays a part ie more on hot days etc. What i would like to know is how much to give on an average day so I can vary it according to the weather. Thanks Mike.

Welcome to the forum Mike.
Not what I grow, but I'm sure some advice will be along shortly.

I think folk are reticent to give you an answer as I doubt there is a precise answer to be honest, it's something that sort of comes by experience, green magic lol

Well, in the absence of any more qualified answer ... I grow mine in 15L bottomless pots, standing on a bed of sand/gravel. I water pretty much daily in summer, about a litre per plant, maybe more in hot weather.

I make sure the soil around the plants is damp ,the worst thing you can do is let them dry out then over water this usually causes the tomatoes to split ,I try not to water to high up the plant it is very tempting to spray the full plant with the idea it will help the flowers to set but it can cause blossom end rot I use a hand sprayer with a fine mist for this , I hope this has helped you although it isn't a complete answer to your question

Like TB says it is impossible to give a definitive answer. Some observations. The usual advice for border grown tomatoes is to flood the bed prior to planting letting it drain before the actual planting. Border tomatoes will always require less water than pot or gro-bag ones partly because of this reservoir. One thing is certain, never wet the foliage only water the bed to help reduce fungal problems. As Robo says, consistency is important to avoid splitting or blossom end rot. If possible water every day but vary the amount to keep the soil just nicely moist. Tomatoes treated a little bit rough by slightly under watering will normally come earlier and have a better flavour. I was going to avoid mentioning volumes but in a bed I'd suggest starting at 1 litre per plant per day with maybe double that for big plants on a hot day but you'll have to judge it by looking at the state of the plants and the soil.

Welcome Mike.

The definitive answer to your question will vary considerably subject to the soil type the tomatoes are planted in and whether the plants are indoors or out.

I grow toms outdoor. My soil is now light, having been clay, thanks to copious amounts of composted manure having been distributed on the plot. There are some pictures on some of my posts of lorry loads being delivered..

I avoid watering on leaves and try and only water at base of plant. I try to imagine how damp the soil would be if it had a drip watering system.
In other words I try to keep them lightly moist. Not always possible so sometimes in summer they do dry out but do try to avoid it.


Following in the footsteps of fellow members:- Normal Disclaimers apply

oh xxxxxx ive been doing it wrong for xx years

i grow toms in the ground in the centre bed of a 30 foot polytunnel.... i use a bog standard lawn sprinkler does half the tunnel at a time, once theres a load of plants established i normally set it going on a sunday morning working up to a nominal hour in summer . if its a really hot spell i may do a top up session one evening mid week.... i like to see condensation on the inside of the plastic... if there isnt any its too dry. most plants seem to prefer hot and moist to hot and dry.

there are no magic numbers, its all about the dryness of the soil and look of the leaves.

richard p wrote:oh xxxxxx ive been doing it wrong for xx years

i grow toms in the ground in the centre bed of a 30 foot polytunnel.... i use a bog standard lawn sprinkler does half the tunnel at a time, once theres a load of plants established i normally set it going on a sunday morning working up to a nominal hour in summer . if its a really hot spell i may do a top up session one evening mid week.... i like to see condensation on the inside of the plastic... if there isnt any its too dry. most plants seem to prefer hot and moist to hot and dry.

there are no magic numbers, its all about the dryness of the soil and look of the leaves.

You must have good ventilation Richard, otherwise so much dampness could invite the dreaded blight to call. I follow the late Geoff Hamiltons advice and damp the paths with a watering can rather than the tunnel/glass walls/roof.

richard p wrote:oh xxxxxx ive been doing it wrong for xx years

I think you might be making a very tongue in cheek comment there, if not then who says so ?.

Maybe that's why so many are now making disclaimers about not being experts, because what has worked for years for one may or may not work for someone else.

I used to put a sprinkler in the pollytunnel and saturate everything in it ,last year I had the dreaded blight I lost a lot of tomatoes it was the first time I had blight in over 48 years of growing tomatoes this year I will be a lot more careful when watering

I use those water spike things in 1 litre plastic pop bottles. I find I fill daily when very hot but find alternate days is fine when not blazing hot. This directs it straight to the roots & it kind of guides you how much - if the bottle is empty fill it, or just top up if not - just in case tomorrow is a scorcher! (We live in hope)!

Hi,

I grown tomatoes outside in a raised bed, along a fence. I only water below the leaves - something about burning them??

I generally water daily with a feed at least once a week. Not huge amounts though as I try and only use what the water butt provides, only the bed they are in seems to retain water well. They are generally ok. But when we're away I pay the next door neighbours lad to water everything. Not sure how much water he gives them but the plants always go bonkers! I suspect he drags the hose over the fence .... probably best now mention this to his folks as we're now on water metres......

Pawty

As most people have already said - it all depends. Younger plants will also need much less water than fully grown ones. I grow our tomatoes in large growbags with growpots screwed into them (three plants per bag). The growpots' deep rim allows you to water straight to the roots and, as I always punch a few holes into the bottom of the growbags, I water until the water starts dribbling out. In very warm weather that might be once a day, on cooler days just two or three times a week.

I've got those grow pot things, but I'm planning on using them with the tomatoes in the soil rather than a growbag. The thinking is the plants will be planted into the pots actually above soil level and will be watered in the ring round the pot, encouraging the roots into the soil. So less worry about water requirements and sure the water and feed goes to the roots easily. I will be able to monitor the soil to check it doesn't dry out too much, time will tell if it works.