Caring for zucchini: watering, fertilizing & diseases

After planting, zucchini need care and nutrients for a bounty harvest. We present common diseases and also give tips on watering and fertilizing zucchini.

the zucchini (Cucurbita pepo subsp. pepo convar. giromontiina)counts like others pumpkins (Cucurbitamaximum, C moschata & C pepo) and cucumbers (Cucumis sativus) also, to the large family of cucurbits (Cucurbitaceae). Zucchini plants with a rich fruit load thank you for good care until late in the year. How often do you need to water zucchini? What is the right fertilizer for zucchini? When is the best time to fertilize? And when can nettle manure help? We give you tips on water and nutrient supply and present the most important diseases of zucchini.

Caring for zucchini plants: proper watering

Zucchini need quite a lot of water to form their juicy, crunchy fruits. The plant suffers when it is dry, withers quickly and produces significantly fewer flowers in the long term. Regular watering is therefore extremely important for zucchini. Depending on the weather, it should be watered once or twice a week. In midsummer you usually have to water more often. The water for watering should never be cold, because the zucchini plant suffers at temperatures below 10 °C. Also, ideally water in the morning. Then the plant can absorb enough water until the afternoon heat to get through the day well. The following applies: Always pour directly onto the ground and do not wet the plant with water, otherwise the risk of fungal infections increases significantly.

tip: A mulch layer of plant materials reduces the high level of evaporation in summer and reduces the growth of weeds. In addition, this offers the advantage that the fruits do not lie directly on the ground when ripe and are therefore less prone to rot. However, mulch binds nitrogen as it decomposes, so you should think about balancing fertilization.

Fertilize zucchini

Zucchini and other pumpkin plants are among the most consuming vegetables. They therefore need comparatively high amounts of nutrients for healthy growth and good fruit set. However, not all fertilizers are equally suitable for fertilizing zucchini plants.

Suitable fertilizer for zucchini

mineral fertilizers how blue grain and Co. are easily soluble and can be absorbed directly by the plant. However, this quick but short-term nutrient boost is not enough for the zucchini in the long run. If used improperly, mineral fertilizers can quickly lead to over-fertilization of the soil and permanently damage the sensitive roots of the plant. It is not uncommon for the nutrients to be washed out into deeper soil layers, where they lead to increased nitrate levels in the groundwater.

Long-term fertilizer with a high proportion of organic matter - like ours Plantura organic tomato fertilizer – are the better choice from a scientific and sustainable point of view. They have many benefits when fertilizing zucchini such as promoting healthy and active soil life as microorganisms feed on organic matter. At the same time, the production of primarily organic fertilizers saves resources and energy compared to the extraction process for mineral fertilizers. For example, in our Plantura organic fertilizers vegetable waste products, such as cocoa shells or vinasse, from the food production and animal feed industry are used.

When and how often should you fertilize zucchini?

The nutrient supply should always be adapted to the respective stage of development of the zucchini plant. In the period after planting, the zucchini needs nitrogen above all to form leaves and grow quickly in size. In the flowering and fruiting phase, priority should be given to the potassium supply.

At a glance: when should you fertilize zucchini?

• After sowing, no fertilization is necessary until planting.
• Before planting out, soak up the garden soil at the planting site compost and enrich mainly organic long-term fertilizer.
• Fertilize after about two months during flowering and fruit formation.

Zucchini can be preferred because the seeds usually germinate very easily and quickly. In order to get strong seedlings, it is advisable to bring the courgettes in the greenhouse or on the windowsill from mid-April. Low-nutrient cultivation substrate is completely sufficient for this. The seedlings are sufficiently supplied with the provisions from the seeds in the first few weeks and do not have to be additionally fertilized. A detailed guide to Cultivation and planting of zucchini can be found in our special article.

To give the zucchini plants a good start, you can incorporate some compost or granular fertilizer into the soil during planting. It is best to use a primarily organic long-term fertilizer with a high potassium content, such as our Plantura Organic Tomato Fertilizer. The fertilizer granules, which slowly decompose over weeks, release the nutrients they contain to plants and the environment in a long-term and gentle manner. After about two months, a second fertilization takes place, which provides your zucchini with the most important nutrients until the end of the season.

Fertilize the zucchini in the pot

In the case of zucchini in pot culture, the incorporation of granular fertilizers is difficult, as the roots are quickly damaged here. For a zucchini in a bucket on the balcony or terrace, we therefore recommend using an organic liquid fertilizer - for example our Plantura Organic Tomato & Vegetable Fertilizer – which is applied together with the irrigation water. The nutrients it contains reach the roots directly and can also quickly remedy acute deficiency symptoms, such as yellowing of the lower leaves.

Pests and diseases of zucchini

Zucchini are generally not particularly prone to disease. With unfavorable growth conditions and especially in wet summers, however, diseases can increase.

The blossom and fruit end rot is a physiological disease due to calcium deficiency. The young zucchini begin to rot from the end. First there is a sunken dark brown area, which quickly widens. The usually slightly acidic garden soil can quickly lead to a calcium deficiency - adding lime to the planting can prevent end rot. Pure calcium fertilizers can supply zucchini plants with the nutrient for a short time and in this way alleviate symptoms that have already occurred. In our article on Blossom end rot on tomatoes you can read more about the symptoms and prevention of the disease, which also occurs on zucchini.

aphids (Aphidoidea) can multiply rapidly in early summer and form large colonies, including on courgettes. Aphids can be controlled with pesticides or beneficial insects. In our special article you will learn everything about the use of Beneficial insects against aphids.

The viral disease zucchini yellow mosaic is transmitted by infected tools, but mainly by aphids. The leaves turn to a mosaic yellow-green pattern and the plant shows increasing stunted growth on the shoots. Infected plants should be completely removed and discarded. The best strategy for preventing the viral disease is the Control of aphids represent.

Powdery mildew (Erysiphaceae) on zucchini initially causes a white coating on the upper side of the leaf, which later spreads to the underside. You should therefore cut back the infected zucchini leaves at the first sign. Never water the plants from above, otherwise the powdery mildew will spread further. For more tips, see our article on Control of powdery mildew on zucchini.

Also the gray horse (Botrytis cinerea) occurs mainly in very humid, warm weather and mainly affects the fruit. Zucchini should not be too close together to guarantee quick drying after the rain. Here, too, correct watering (only directly on the ground) is crucial in order not to spread the spores of the fungus further.

tip: A home remedy for fertilizing zucchini forms the nettle manure. It not only promotes growth, but also the zucchini's resistance to diseases. Sprayed undiluted, it repels aphids and other insects.

Ideally, the zucchini will bear the first fruits from the end of June and can be harvested soon afterwards. We give you tips on the right one Harvesting and use of zucchini.