- Tomato plants need lots of water
- Tomato plants are hungry feeders
- Pinch out the flowers
- Tomato plants like a drop of rain
All of these statements are true and untrue.
On the basis of the above, an enthusiastic beginner will bring his or her seedlings home from the garden centre, keep them stood in a tray of water, start feeding tomato food, remove the flowers when they arrive and leave their young plants out in the rain!
The truth is, tips and advice are often only relevant to a particular period or situation in a plant’s growth.
I’ve had people ask if they should pinch out the flowers!
Surprisingly, there are times when removing flowers is a good idea:
- On beefsteak varieties to reduce the number of flowers on each truss – this reduces the load on a plant and makes for a more consistent and larger size fruit.
- When taking cuttings – to keep a plant in its vegetative mode and prevent it from flowering before it has reached a decent size. This is particularly useful when taking cuttings from bush varieties because as soon as they start to flower, their energy goes into flowering and fruiting. You won’t get many tomatoes from a 4 inch cutting!
I sometimes hear people say … “tomato plants like a drop of rain”.
That’s also true, but they prefer it around their roots rather than on their leaves!
Nutrient Uptake
Rain water has a low/acidic pH value and tomato plants like soil and water with a pH that is slightly acidic rather than alkaline. When pH is in the best range for plants, they are able to absorb the widest range of nutrients. If pH is too high or low, plants will not be able to absorb the full range of nutrients they need.
Those who grow in potting soil (such as multi-purpose compost) needn’t worry too much about pH because a good quality potting compost should contain buffers that keep pH within a reasonable range.
However, if growing in the ground or using old soil, when nutrient deficiencies display on a plant’s leaves, it could be a good idea to check the pH value of both the soil and the tap water that plants are receiving.
Nutrient balance
The important thing to remember about pH is that it effects the uptake of nutrients and we want our plants to receive the whole range – all the nutrients they need.
Temperature
Low temperatures can effect nutrient uptake too. We often see a purple tinge on the underside of lower leaves in the early spring. The fact that it is displayed on the lower leaves tells us that the nutrient deficiency may be a mobile nutrient (see nutrient mobility in articles above) or temperatures are just too cold to absorb any nutrient.
We needn’t worry about this because as temperatures rise and days become longer, the deficiencies are corrected.
Nutrient Blocking
Sometimes, especially later in the season when soil has received a lot of feeding by synthetic foods such as Tomorite, some nutrients are able to block the uptake of other nutrients. This is caused by an imbalance – too much of one and not enough of another and is an issue that is particularly difficult to put right.
One of the advantages of giving additional nutrients by foliar feeding is that we don’t cause an imbalance in the soil.
Container Soil
Once container soil has a nutrient imbalance, the only option is to “flush” with tepid water and hope to remove as much of the nutrient content as possible, and start again.
Ground Soil
Of course it’s difficult to flush plants that are growing in the ground – another good reason for giving organic feeds so that nutrient problems are much less likely to occur.
Foliar Feeding
We can also correct nutrient deficiencies by foliar feeding.
It is possible to buy every single nutrient separately, but would be expensive to do so!
The method I use, is giving a balanced feed for seedlings that contains every nutrient needed and at the right amount. Think of it as baby food.
One of the biggest advantages of giving a complete food is that it eliminates the possibility of a nutrient deficiency. A quick spray and you know that your plants are getting every nutrient they need.
Nutrient Tonic
I also use it as a foliar tonic for mature plants – if nutrient problems occur, this is one area that is easily sorted.
If you are interested in buying a seedling feed then the least expensive way is to visit a local hydroponic shop and buy either “First Feed” by Rootit, “Plant Start” by Vitalink or “Formulex”.
Rootit Sponges in trays are one of the best ways to germinate seeds and encourage rapid healthy growth in seedlings.
I’m always happy to answer any question you may have about tomato growing at [email protected] or in the comments below.
May the sun always shine on your seedlings!
Regards,
Nick
There are many different ways to germinate and propagate seedlings including: using compost, jiffy pellets, rockwool cubes, vermiculite and sponges.
The best methods are those that contain plenty of air and hold moisture at the same time. Using “value” seed or multi-purpose compost is good but you will get better results from vermiculite, rockwool or sponges.
If sowing expensive hybrid seeds, it would probably be best to use the better options.
Les
Hi! I have just moved to Spain on the Costa del Sol and I thought that I might take advantage of the large amount of sunshine that I get here almost all year round but I only have a small area outside on the patio, so I have bought 3 small slender window box type to grow some cherry tomatoes in! Which would be the best seeds to sow and have you any tips on what is best ‘to-do’ and what is best ‘not to-do’? Cheers Les
Nick
Hi Les,
Tomato varieties that are suitable to grow in your area are probably going to be found on sale in the local market from which you can probably take seeds, or at a local garden centre. It’s often the case that varieties that perform well in the UK are disappointing in warmer climates.
For window boxes I recommend a small bush or trailing variety and a regular water supply so that the soil won’t run dry.
Nick
kevin
Hi Nick how many plants can i grow in a 8×6 greenhouse keep up the good work.
Nick
Hi Kevin,
I would lay grow bags around the greenhouse end to end and have two large pots for bush varieties down the middle.
Three cherry varieties in each grow bag or two medium or large varieties.
Removing lower leaves for good aeration when possible and keep condensation to a minimum with good ventilation.
Nick
Rhys Jaggar
Nice summary as usual Nick.
One thing I’ve tried in the past week or so with my early plants and then with my main bunch sown a month later is to dose them with a diluted version of ‘Maxicrop’, which is a liquid seaweed extract concentrate. I diluted it 4 times more than you might normally use and treated plants in 15cm pots (about 15cm tall and 15cm wingspan) with 150ml and those in 8cm pots with 30 – 40ml to see the effect it had.
All plants have grown much more rapidly in the past week but the smaller plants may also still have a slight nutrient deficiency (based on the purple hue of the underside of leaves).
The other experiment I was trying was seeing at what point it becomes worthwhile to provide more water to the tomato plants (balancing the risk of cold and wet being bad with wet and warm being good). For my early plants, at 6 weeks post sowing, I dosed them all in 15cm pots with 100ml of rainwater and they grew measurably faster than before, when I was merely watering once a week from underneath by capillary flow/osmosis.
I only did this because the March this year has been so much milder than in recent years – we already have flowers on our plum and cherry tree and the pear trees are now starting to leaf also.
Nick
Hi Rhys,
We’re in for some warm weather so it will be good for a change to give them plenty of water and not have to worry about cold wet compost.
I think that seaweed is one of the best organic options available and really helps stimulate growth.
Sounds like your plants are doing very well.
Cheers,
Nick
Rhys Jaggar
First flower on Maskotka today, April 3rd.
Ridiculous how different this spring is to last year’s!! 57 days to first flower after sowing seeds a month too early!! What would happen if I actually sowed them on the right date?!