It’s at this time of the season that I receive emails about the success’ and failures that people have experienced this year.
It’s been a good season in my part of the world, mainly owing to a dryish summer and the only problem I had was late pollination with some of my varieties.
However, north of the border it’s been a dull and damp season for many. So here are a few ideas about how to increase the chances of a successful crop – tips that may come in handy next season, wherever you are!
Minimising The Risk of Disease
We all know that tomatoes need warmth and sunshine to produce a good crop, but is it possible to get results in a poor season and short season area?
So what can be done to minimise the risk of disaster – or perhaps I should say, maximise the possibility of success!
Choosing The Right Varieties
Varieties like Moneymaker, Alicante, Gardener’s Delight and Ailsa Craig have been popular in British gardens for years, but in a poor season aren’t the most likely varieties to produce a good crop.
Also, many gardeners have yet to grow bush varieties and think that cherry tomatoes are just too small!
I can say that in my experience, bush varieties will mature quicker than tall varieties, and cherry toms will mature more quickly than medium or large tomatoes.
Find a quick maturing, short seasoned bush/cherry variety like Red Alert. Red Alert, when performing well, will produce larger than average cherry tomatoes and the taste is excellent.
Getting Off To A Good Start
Developing healthy plants with strong immune systems will go a long way to delaying the inevitable blight!
Tomato plants are like humans in the sense that if they are in top condition, they are less likely to fall sick if there is a cold going ’round. For tomato plants, it’s usually fungal infections brought about be rain, condensation or infection from other tomato plants that infect them and slow down their growth and eventually reduce the amount and size of tomatoes they produce.
The best product I’ve used to help seedlings and young plants is Liquid Seaweed Extract. It’s organic and helps stimulate the immune system – if it tasted better I’d probably drink some myself! (not that I’ve tried it of course!)
Balancing Greenhouse Condensation With Aeration
Rain and wet leaves is the biggest threat to outdoor grown tomato plants, but plants in the greenhouse can also be at risk from condensation. Wet, damp air with no circulation will also make tomato plants vulnerable to fungal diseases.
Greenhouse Heating Is Expensive
Obviously a greenhouse heater would do the trick, but its expensive, however, one of the less expensive options would be to have an economy heater on a timer. This would take away some of the condensation that gathers first thing in the morning and create an airflow of rising heat to circulate the air.
Deleafing To Improve Airflow
Another way to help improve airflow is deleafing tall varieties – below the first truss to start with then below each truss when it begins to produce ripe fruit.
Keeping the greenhouse door slightly open at night is an option – it is better to have plants a degree or so colder if it keeps the condensation away.
Also, growing less trusses will also give you a crop sooner and a lower yield of ripe tomatoes is better than a higher yield of green tomatoes – unless it’s a green variety of course!
Feeding for Optimum Growth
This is an area of some difficulty … tomato plants won’t absorb nutrients in cold conditions however much you give them! The reason is because they don’t need feeding, because in cold weather – they don’t grow!
Underground – Overground
One tip about feeding is that it is always best not to give anything but tomato food through the roots – keep all supplements like magnesium and calcium for feeding through the leaves – foliar feeding.
The reason is because too much of one nutrient can totally block another nutrient from being absorbed by a tomato plant’s roots. If everything goes in the soil, it can get complicated down there!
Growing tomatoes outdoors or in a cold greenhouse, is a big challenge in a short season area. It seems to me that the quicker you can get a plant to produce ripe tomatoes the more chance you have of success. However, plants may need help along the way, from a little extra heat or circulation to cut down the condensation.
Also, help to boost their immune system to help fight off diseases, and if all else fails, a fungicide like Dithane to help stop blight from spreading out of control.
Here’s a list of products that can help in a poor season.
Liquid Seaweed Extract – helps boost immune system and growth.
Crop Aid – a product that I haven’t yet tried, but suggests that it can help against damage from the cold???
SP Plant invigorator – similar to Liquid Seaweed but also helps prevent aphid attack in the greenhouse
Dithane 945 – the last resort but it will stop blight from getting worse and spreading to your other plants if used in time.
If you have any tips please leave a comment below.