Pruning eggplants is often debated on many gardening forums. As a somewhat laid-back gardener, I can see the benefits of both sides of the argument. Any amount of pruning can increase light, air flow and new foliage growth at the same time as decrease the risk of pests and diseases. It can also make it easier to weed and to keep an eye on the developing fruit.
But how much pruning is really necessary? From what I have read and experienced, this depends on what kind of eggplant you are growing, where you are growing them and what your local conditions are. Below I have briefly explained the different pruning stages, given a few reasons why and situations where you may (or may not) prune your eggplants.
Pruning eggplants during planting
Pruning your eggplant when transplanting out your seedlings into the garden bed is definitely necessary and just a matter of pinching off ALL of the flowers. This will encourage the plant to produce roots and leaves instead of fruit at this very early stage. It’s important for the fruit to have some canopy cover as they develop, so encouraging bushy growth and healthy roots is important at this stage.
Use a high nitrogen fertilizer to encourage foliage growth during this stage.
Pruning eggplants during growth
As the plant becomes established in the garden bed, remove any dead, damaged or diseased leaves. Coincidentally, these are usually the lowest leaves on the plant anyway, which means you are improving air flow around the base at the same time as encouraging canopy growth and reducing the risk of infecting the plant from soil borne fungal spores.
About 2 weeks after transplanting out my eggplant seedling into my garden bed I go through and tip prune them. I find that removing the fresh new growing tip, especially on the Asian varieties, encourages a bushier canopy which protects the fruit from getting sun burnt.
Some people prune back their standard, globe eggplant to 3 – 4 main stems once they are well established but before flowering. This strengthens the remaining stems in preparation for the heavy fruits in addition to increasing air flow and encouraging canopy growth. Greenhouse trials show that pruning your eggplant back to 3 – 4 stems can increase quantity, improve color and speed up ripening.
I personally opt for tip pruning and staking instead, (which is pretty much a necessity for most of the Asian varieties that I grow), but I can see the benefit of a heavier prune in locations that aren’t as sunny and may have a shorter growing season.
For maximum production and fruit size it’s recommended to remove any suckers, just like you would on a tomato plant. These mainly form in between the main branches and can usually be pinched off easily. Just like on tomatoes, it’s not crucial to remove every single sucker at once and in my lazy gardening approach, I tend to pinch a couple off every now and then as I stroll through the vegie garden.
Pruning eggplants during fruiting
When the fruit are developing nicely, some people use this time to lift prune the stem of the plant. This means removing ALL of the leaves that are below the first fruit or flowers.
I personally find that the small amount of pruning here and there during the growth stage is enough that I don’t need to lift prune my eggplants at the fruiting stage, but this is an important step if you have had any diseases in your eggplant crop in previous years or are in areas with a high humidity. In these two situations, there is a need to increase air flow and to minimize the risk of pests and diseases reoccurring by reducing the chances of spores landing on the lower leaves.
Varieties of eggplant that produce large fruit, such as Black Beauty, benefit from only having 5 – 6 pieces of fruit per plant. This means pinching off any additional fruits while they are growing. Limiting the number of fruits per plant decreases the risk of the branches breaking under their weight. I have found that the varieties that produce smaller fruit, such as the Thai varieties, don’t require any flowers to be pinched off during the fruiting stage.
Pruning eggplants during harvest
If you have enjoyed an early harvest (check here to know when eggplants are ready), and believe you have enough time to squeeze in another crop, then grab your shears and give the plant a good once over; removing all of the suckers, lower leaves and damaged leaves, but try to leave as many flowers on the plant as possible. For me, this is usually when the veggie patch is starting to look a little wild, and a good clean up can really re-vitalize the garden after a long, hot summer.
This is also a good time to give your plant a little feed. Commercial growers use a high potassium fertilizer at this stage (NPK: 14-5-26).
Pruning eggplants at the end of the season
Just like all the other vegies in the garden, eventually the cold weather will knock your eggplants around. But before the cold weather strikes, you should top your eggplants at the same time and in a similar manner as your tomato plants. Removing all of the flowers approximately 3 – 4 weeks before the night time temperatures are consistently below 50 °F (10 °C) will ensure the remaining fruit have enough time and energy to develop before the first killer frost.
In mild or tropical climates, eggplants can be grown as a perennial, which means they benefit from a thorough prune at the end of each fruiting season.
In Summary
Growing eggplant, like most other vegetables, doesn’t need to be arduous but every plant benefits from a bit of a prune occasionally. It seems like the amount of pruning depends on a number of factors which are summarized below;
- When you first transplant the seedling (prune flowers only).
- When you are growing a variety that produces big, heavy fruit (prune stems and leaves, then later developing fruit).
- When your climate only has mild summers and there is little risk of sunburnt fruit (prune stems and leaves).
- When you have had previous problems with diseases (prune lower stems and leaves).
- When you are trying to keep your plant compact (prune stems and leaves).
- When any leaves touch the ground (prune leaves).
- When sucker starts growing (prune stems and leaves).
- When the cold weather is coming (prune flowers).
- When you are growing your eggplant as a perennial (prune stems and leaves post-harvest).
