Crop Failures: Where did I go wrong?

The great thing about gardening is that we can look at what happened, how we can improve, seek advice and try again next season. Every year puts out something new for us to improve on and every year we learn something new. As gardeners and people who love plants and fresh produce, we are constantly learning from ourselves, from nature and from each other. Crop failures can be the result of many factors, we outline some of the most common below:

Poor soil

Planting in poor soil can cause all sorts of problems. Not enough nutrients can mean that your crop does not have enough nutrients to keep those leaves green and put energy into the fruit of the plant either. Ensure you prepare the beds before planting, or in the case of pots ensure you have a good quality potting mix in the container.

Bulk up the garden with lots of compost and organic matter. I am a big fan of sheep pellets because they break down over time and they are full of nutrients and can help the soil retain the much-needed moisture over summer.

Soil structureCrop failures - carrots

This one kind of fits under the category of poor soils but with so many people growing deformed and small carrots or potatoes it may be something to take note of! The reason we get these deformed carrots or root crops is that the soil needs to be light and aerated, smooth and free of clumps. When the soil is too hard it is not as easy for the root vegetable to push through the soil resulting in a deformed crop.

Wrong position

The wrong position in the garden can mean a big difference in the crop you will harvest. Plants such as capsicum, chillies and eggplant require full sun and warmth to set fruit, whereas cucumbers can benefit from some protection from the afternoon sun, so they don’t get scorched. Most vegetable crops require around 6 hours of sunlight but keep in mind just how hot things can get in that position, especially when growing things in containers. Containers warm up quickly so in many cases they may need to be shifted to somewhere a little cooler where the soil won’t dry out as quickly.


I have been noticing a trend when things happen to go wrong in the garden, in my opinion the number 1 thing people have problems with is watering, either too much or too little. Watering can be such a hard thing to get right. If you have had bitter tasting cucumbers or dry fruit on your fruiting plants, this may mean that you are not watering enough throughout the season. Try watering a little more, especially when flowers bloom and the fruit set. When watering try to avoid overhead watering or watering on the foliage of the plants, plants such as cucumber can be affected by powdery mildew and other fungus.

Mulching can help with water retention and acts as a barrier from that hot sun drying the soil out too much.

Not Enough space/ overcrowding

Overcrowding vegetables can block out the sunlight which means that some veggies won’t be getting the light they need to produce a good size crop. I had my own little crop failure this year on one of my chilli plants. I planted it too close to my tomatoes that got very large and blocked out the sunlight resulting in one lonely chilli on my plant. It happens to all gardeners and often having a good garden plan can eliminate this issue. It is very easy to get carried away when planting out new seedlings but try and remember how big the plant will get in a few months’ time. You want air to be able to flow in between the plants so we don’t get fungal diseases.


I have had a lot of people asking about yellow leaves this summer and for the plant to thrive and produce a good crop they need to be well fed. Although the soil may have been full of goodies, our vegetables deplete the soil as they grow and feed. Top up with sheep pellets or a slow release fertiliser such as Tui Novatec Premium depending on your preference and gardening style. Novatec is also safe for use in pots. I also like to spritz the foliage with a liquid fertiliser every week. This will give your plants a boost. Tui Seaweed Organic Plant Tonic has been my go-to of late.


If you have been in a situation where you have only gotten one or two zucchinis, the problem may be there just hasn’t been enough pollination. Try planting more ornamentals and bee attracting plants next time you grow your crop and if you are feeling up to a bit more work in the garden hand pollination can also have great results.

Tips for success

  • Crop rotation

It is a good idea to try the practice of crop rotation. The idea is that you will not grow the same vegetable in the same place next year. This can prevent soil borne diseases, ensure that the soil will not be depleted of nutrients and help keep it balanced. Some crops such as legumes are nitrogen fixing and will help add nitrogen to the soil, after legumes try planting brassicas which are very nitrogen hungry. Never grow tomatoes or potatoes in the same spots, they are in the same family and can get diseases quickly if grown year after year.

  • Green manure crops

If you have nothing planned for your winter veggie garden, a good idea is to plant a green manure crop. This will help add nutrients back into the soil, prevent the soil from drying out, adds humus, aerates the soil and controls weeds. This will then help your summer veggies thrive in the season to come. It is especially beneficial to grow a green manure crop where you have had gross feeders such as zucchini, squash or melons planted. Bring that soil back to life!

  • Feeding the soil feeds the plant

Keep the soil fed and this will help the plant thrive, it will also help keep those pests away. Healthy plants mean less bugs!

  • Mulching

This is a great way to help with water retention and will also add to the soil structure as the mulch breaks down, a must do in the garden.

  • Plan your garden

Creating a plan will eliminate over-crowding, help you get the best results and make sure your plants are in the right position. Look around, take note of where the sun comes up, how warm, or how much shade the garden gets and make a solid plan. It is a fun thing to do.

  • Don’t overfeed your potatoes and root crops with nitrogen

Too much nitrogen for root crops will feed the tops and not the bottoms, try a potato food for your crop instead. Ensure the soil is loose and aerated, this will help you get less deformities in your crop.

  • Garden Hygiene

Remove any dead or dying foliage throughout the season, this will prevent the spread of disease. Be vigilant and act fast if you see problems arising.