John Binion
The original tomatoes are a subtropical fruit from South America. As such, they appreciate some warmth. Daylesford is not subtropical. Nevertheless, over time some varieties have been bred to cope with a cooler climate and short growing seasons. The climate conditions for Daylesford and surrounds are challenging to some extent for growing tomatoes.
What to grow
There are a number of cool climate, short season, open pollinated heirloom varieties such as Black Russian, Siberian, Green Zebra, Yellow Pear, Rouge de Mormande and Tommy Toe which are suitable for Daylesford and the surrounding areas.
There are many F1 Hybrid varieties available from nurseries. These are vigorous in their first year but do not collect the seed. It’s a waste of time. The plants will definitely not be as good as the parents in subsequent years. Good hybrids that do not mind the cool are Apollo and Apollo Improved.
Some of the stall holders at the Daylesford Sunday Market sell heirloom varieties that are also suitable. Some varieties do not go bright red when they are ripe. The yellow, green and purple varieties can actually taste more delicious when eaten than the red ones. In contrast, some red varieties are as exciting as eating blotting paper.
An example of an unsuitable variety for Daylesford is Grosse Lisse. It is more successful in Melbourne because it prefers warmer conditions than we have in Daylesford and surrounds.
There are hundreds of varieties available in Australia. Do some research to find others that might appeal to you and might be suitable for our climate. A good starting point is the Sustainable Gardening Australia list of tomato varieties.
When to plant
“Plant tomatoes on Cup day” is the wisdom but the “wisdom” probably applies more to Melbourne. Late November is a better to plant tomatoes in Daylesford because of the possibility of late frosts.
How to plant
Plant seedlings in a sunny position, very deep, with only the top few leaves showing. The reason for deep planting is that the plant will produce roots on the covered portion of the stem and be more vigorous. Do not tamp the soil heavily for a few days until the plants have settled.
The soil should be composted. The matter of fertilising is a total subject in itself. To keep the soil moist, mulching is important. An excellent mulch is quality 2nd or 3rd cut Lucerne. It may seem expensive but its nutrient benefit is much greater than Pea straw, for example, and there is more in the bale. If you can get the large round or big rectangular bale it is definitely cost effective.
You can surround the plant with plastic bottles filled with water to provide a thermal mass to create a warmer environment while the seedling is young.
For tall varieties, put a stake in when you plant. If you stake later, the stake can damage the roots.
Growing
When the seedling grows and there are three strong nodes, pinch the growing point. This will give you six laterals that will develop and over time will need to be tied to the stake.
The plants need regular and consistent watering. This is an important consideration. Dry soil or watering too much in the evening can cause blossom end rot which is a brown mark at the base of the fruit. It is a result of insufficient calcium uptake and can be remedied by giving the plant a calcium hit by spraying it with a powered milk solution.
To set fruit, tomatoes need warm night time temperatures. If it is too cold at night, nothing happens with the flower so they are not fertilised. No fertilisation – no tomatoes. This is probably the main issue with poor plant productivity in Daylesford. With a small paint brush, you can try to dust tickle the flowers to transfer pollen to enhance fertilising and fruit set.
Tomatoes can be grown in very large plastic pots with a good soil mix. In the context of warmth, growing in a poly tunnel can be very beneficial if you have one available.
Preparing for next year
It is important to remember that tomatoes should not be grown in the same soil from year to year as root knot nematodes will develop and infect the plants in subsequent years. A companion plant for the partial control of nematodes is the marigold. It is best, though, to practise crop rotation – plant tomatoes in a new soil area and wait a few years before going back to a previous planting area. Also, when you take out the plants at the end of the season, remove the root ball to reduce the nematode potential.
John Binion is a gardening enthusiast and is the Secretary of the Daylesford Horticultural Society.