Pruning gardeners' favourite

Pruning gardeners' favourite

By Lidia Boque Gousgouni
06 Dec 2017

Visit any well-stocked nursery at this time of the year and you will discover a seemingly endless choice of the gardeners’ favourite – the tomato. They come in just about every colour from white to purple and striped, every size from cherry to beefsteak, and many cultivars from heirloom to hybrid. But all tomatoes fit into one of two growth habits; determinate or indeterminate.

Determinate: These are also referred to as ‘bush’ tomatoes. Examples are Ballerina, Roma, Burnley Gem and First Prize. They will grow to about one meter and set fruit which will ripen around the same time – usually within a couple of weeks. This variety requires minimal staking as it forms quite a compact growth habit. This makes determinate varieties perfect for baskets, pots or containers for patios or balconies. As all the fruit is available for harvesting at the same time, this variety is a great choice if you plan to make sauces, salsas or soups where large quantities of fruit are needed.

Indeterminate: These are also referred to as ‘vining’ tomatoes and will grow to two to three meters and more. These tomatoes produce an abundance of fruit throughout the season until the frosts come. They require substantial staking, training or caging and examples are most Cherry and heirloom varieties. These varieties are ideal for salads as they can be harvested and enjoyed over a long period of time.    

Maximising your crop means pruning, but only prune the indeterminate varieties. These varieties naturally produce more leaves and flowers throughout the season unlike the determinates. Pruning determinate tomatoes will reduce your harvest.

Pruning indeterminates is easier to do on tomatoes that have been trained or staked as you are able to inspect the growth easily. Firstly, inspect the leaves and remove any that touch or are close to the ground – they act as a pathway for pests and disease.

Next – consider thinning out dense foliage. All plants need sunlight to create energy and tomatoes need an abundance of light to thrive. If the plant is using more energy than it’s producing the leaves may turn yellow and drop.  So, trim off leaves that shade or crowd other leaves, just don’t be too zealous.

Finally, once the tomato has flowers, inspect the plant for suckers and remove them with clean secateurs. Suckers can be found growing in the axis between the main stem and the branch. They will eventually grow leaves, flowers and fruit but will compete for nutrients from the main plant resulting in smaller fruit.  If your plant is healthy a few suckers may improve the yield – and as a bonus, any suckers removed can be used as cuttings and grown into new plants.

Diary – If you’ve been thinking about studying horticulture – Wodonga TAFE has Certificate III in Horticulture timetabled to begin at the end of February 2018.  Why not call into Wodonga TAFE’s horticulture department in University Drive, Wodonga and pick up a timetable for 2018.

Photo – You can clearly see the strong growth in the axil of the leaf and stem (growth being held). These are the growths that should be removed on indeterminate tomato plants.

Written by

Jill Owen  (Certificate III in Horticulture student)


By Jill Owen  (Certificate III in Horticulture student)