Here in Ballarat the vegetable gardening Holy Grail is to get ripe tomatoes by Christmas. Yet gardeners often tell me that they struggle to get ripe fruit by February, let alone Christmas. This page gives you some hints on how to produce early season tomatoes.
There are two main reasons why tomato plants can be slow to set fruit.
To set fruit early you need to grow tomato varieties that are early cropping and suited to your local climate. For example, here in Ballarat (which is in the Cool Mountainous climate zone) Rouge de Marmande (early cropping variety that likes cooler conditions) will produce ripe fruit a good three to four weeks earlier than tomato varieties such as Grosse Lisse. Seek out early fruiting tomato varieties and consult with experienced local food gardeners as to what varieties of tomatoes do best in your area.
Though note that early fruiting tomatoes may not be the most productive or best tasting. It is best to grow a number of tomato varieties in a given season.
If conditions are good (well manured soil and plenty of water) tomato plants will put most of their energy into growing laterals at the start of the season, and very little into producing fruit. It is not until late summer/early autumn that they switch to putting most of their energy into fruit. However, if conditions are not good, they will put more of their energy into producing fruit in the early stages.
The trick to getting early tomatoes is to stress the plants a little to encourage fruit production, but not enough to reduce overall yields by stunting growth.
Start your tomato seedlings early using a heated propagation unit and pot them up to large pots in a greenhouse so that when it comes time to plant them out after the last frost the plants will already be large.
LEFT: Tomato seedlings being grown in an aquarium heater propagation box. RIGHT: Tomato seedlings in my greenhouse after they have been potted up into 14cm pots. For more information on the benefits of potting tomato plants up see: Potting Up Tomato Plants.
PLANT INTO GROUND WITH LITTLE OR NO FERTILISER ADDED
Tomatoes planted into soil with low nutrient levels are more likely to set early fruit than ones planted into heavily manured beds. Add manure once some fruit have set to encourage large fruit and vigorous growth.
LET THE TOMATO PLANTS DRY OUT
The easiest way to stress tomato plants is to let the bed they are in dry out to the point where their leaves droop a bit. Plants that are stressed because of lack of water will set fruit much earlier than ones that are not stressed.
DISTURB THE ROOTS
While I have never done this myself, one method used by traditional vegetable gardeners to encourage early tomatoes is to dig up one or two established tomato plants and then replant them straight away in the same spot. I am told that the stress this puts on the plant’s roots encourages them to set fruit much earlier than plants that were not dug up.
The problem with stressing tomato plants in the ground by letting the bed they are in dry out is that if it is a wet spring it may not be possible to get the bed to dry out. While I have stressed tomato plants in the ground in the past these days I prefer to stress them while in pots prior to planting out.
To do this, when seedlings I am growing are large enough I pot them up into large post and place them in my greenhouse. Then at some stage I stress them by letting the pots dry out a little. By stressing them in this manner they will usually have set some flowers by the time they are planted out. Those flowers will then go on to produce early fruit.
LEFT: Tomato plant in a 14cm pot with some flowers on it. This pot had been deliberately let dry out a little to encourage the plant to put on flowers. RIGHT: Closeup of the flowers. When the plant is finally planted in the garden it will already be well on the way to producing early fruit.
Stressing tomato plants weakens them, and weak plants are more susceptible to pests and disease. So, it is important to only stress some of your plants and not to stress them too much. But tomato plants are tough, as long as you do not overstress them, they will go onto produce a normal healthy crop, as well as an early one!
