Tips for Growing Carrots in GreenSmart pots

Carrots originated in the vicinity of Afghanistan several thousand years ago as a purple vegetable. Later, Dutch breeders bred the orange versions we now associate with carrots. In addition to orange carrots you can also choose purple, white and yellow varieties. Ball or block types grow to about five cm in length. Stump-rooted varieties grow to 20 cm. Baby carrot varieties have been bred to be fast growing, small and sweet.

Here are three secrets to growing carrots in GreenSmart pots:

  • Fine soil
  • Soil that is not too rich,
  • Soil temperatures above five deg C when the seeds are sown. Best growth is between 16 & 21 deg C.

Growing Carrots in a GreenSmart pot

Growing Conditions

Sow during September to May. In frost prone areas, plant after last frost date. They do best in a sunny spot with a minimum of shade.

Growing carrots require good drainage and soil depth at least as deep as the maximum expected length of the carrots. Take care to not use potting mix that has previously been used for another root crop. The potting mix must be free of lumps and clods which might deform the tap-roots when they are still growing.

Soak the seeds in water for six hours before planting. I find that it is better to use a two cm thick layer of seed raising mix on top of the potting mix. Bury the seeds to a depth of 0.5 cm and press down to ensure that there is good contact between the seeds and soil. Keep the soil moist during the first two weeks. Seeds take about two weeks to emerge.

When the seedlings have two leaves ruthlessly thin them to being about three cm apart. A month later thin them out again so no two plants are growing side-by-side. Water the plants from above – both before and after thinning. After this, avoid surface watering as you want the tap roots to seek out deeper water from the water reservoir. The idea is to aim to end up with about 60 carrots in a large GreenSmart pot. Some gardeners are able to transplant the thinnings. I have never had much success with the transplants.

An alternative planting technique is to mix radish and carrot seeds together. The radishes grow quickly and will be ready to eat in just a few weeks.

The free draining nature of the GreenSmart pot creates ideal conditions for growing carrots.


It is best to use soil that has previously been enriched with good fertilisers. (eg blood and bone, wood ash, well aged chicken manure pellets) Don’t add fresh fertiliser immediately prior to planting as it will result in forked carrots like this one.

growing carrots

Apply liquid feeds into the water sight glass but don’t overfeed – especially with high nitrogen fertiliser. Too much nitrogen will result in excessive leaf growth.

Pests and Diseases

Carrot rust fly is the main bug to watch for particularly in warmer areas of NZ. The fly is four to eight mm long, shiny black with iridescent wings. They are attracted by the smell of carrot foliage – particularly when the leaves are bruised during thinning. They lay eggs near the carrots and the maggots wriggle into the roots of the carrot. Try spreading coffee grounds alongside the rows. As these flies are  poor fliers – they cannot fly more than 75 cm above the ground – it is a good idea to raise your pots up onto a bench so the carrots are more than 75 cm above ground level.


Good companions are: radishes, white onions, garlic, rosemary and sage. The strong smells of these plants help to repel carrot rust flies. Avoid growing carrots around parsley, celery or parsnips.


Selectively pull up the larger carrots as they mature and allow the smaller carrots to expand into the gaps. Green tops on the carrot roots are caused by sunlight reaching the tops. Avoid by ensuring that the maturing roots are covered with potting mix.

growing carrots and harversting

In the Kitchen

Carrot cake is one of my favourite cakes. Try this recipe from Annabel Langbein. Click here for Carrot Cake by Annabel Langbein.

Carrot juice has many health benefits. My grandmother drank so much carrot juice that it turned her skin colour to pale yellow!!  Here are two websites to check.

What are the Health Benefits of Drinking Carrot Juice? – wiseGEEK


Happy gardening,