Getting your soil ready for carrot planting
Carrots have different land preparation requirements compared with other vegetables. Most growers feel that one has to perform deep ploughing to accommodate the deep root system, and I initially also thought this and purchased a Nardi plough to be able to do very deep tillage.
It worked, but this does damage to the soil and humus in the soil in the long run. Sure, the soil needs to provide easy access for deep root penetration, but there are other ways to achieve this without harming the soil.
Avoid Deep Ploughing
You first need to determine the compaction status of the soil to the depth that the roots will reach.
A good way to do this is to use a soil probe. There are some commercial units available, but you can also make one out of a steel rod of 12mm in diameter and add a handle at the top end, which will be used to push the rod into the soil.
You can push it into moist soil and check for resistance, which could be from a plough pan or a natural hard layer.
One option is trying to plough through this layer, but apart from not being beneficial for the soil, this will also be rather expensive to do.
In this case, the best solution is to pull a ripper through the land to crack this hard layer for root and water penetration.
You can incorporate fertiliser into the top 25cm of soil when preparing for planting. You don’t need to overwork this profile, unless there are fairly large, hard clods.
Optimal planting practices
It is just the surface area where you need a finer texture so as to accommodate the planter and enable it to get all the seed covered for an even stand.
By overdoing it, you can get crusting after a heavy rain. If the soil tends to crust, you can apply a light dressing of gypsum broadcast after planting.
The surface just needs to be fine enough to cover all the seed, but it can be beneficial to have the soil a bit rough, with small clods, when planting in hot weather.
A hot soil surface will affect germination, and by having a larger surface area by not pulverising the top layer, the evaporation will contribute to a cooling affect as the moisture evaporates.
Usually, all you have to do is cover the seed, but in hot conditions, it may be better to set the planter to place the seed a little deeper where the soil is slightly cooler.
The risks are that with a heavy rain and some degree of crusting, this makes it more difficult for the plants to push through the soil surface.
The soil type and condition will determine what the preferred planting depth should be. As a rule of thumb, plant as shallow as you can get away with.
Most carrots are planted on raised beds, which mean that you get the maximum topsoil in the area where the roots are active. The raised beds can be angled so as to remove water from the land when excessive rain falls.