The first cucumbers coming out of the flower beds and greenhouses are crisp and juicy, something all gardeners look forward to. But not everyone knows that overfeeding cucumbers can be dangerous. Sure, watching cucumbers grow taller and put out more leaves before your eyes makes you want to help them at the start of summer. But you should always try to do so in moderation. It is necessary to limit the amount of feeding to a minimum and to rationalize it according to the condition of the soil and the plant itself. How to Fertilize Cucumbers in Early Summer, and when they really need these feedings, I will talk about in the ThumbGarden article.
Fertilizing Cucumbers in Early Summer – is It Necessary?
The early summer is a special time for active cucumber growth. It is true that cucumber plants need a lot of nutrients to grow properly. But before flowering and fruiting, the plants are still using the “starter” resources stored in the soil when preparing the planting beds. And under normal conditions, they should be able to continue to do so. When bushes that have lost their freshness continue to flower and fruit after the busy season of late summer and early fall, it is often necessary to apply additional fertilizer to cucumber plants.
To find out if you need to feed your cucumbers in early summer, all you have to do is answer one simple question – how well was the soil fertilized before planting? And there are only two options.
- If the good quality organic matter was added to the soil, the warm bed was correctly arranged, and the topsoil in the greenhouse was replaced with compost, then fertilization is only needed if the plants themselves are giving signals – pale, misshapen leaves, poor growth.
- If the soil is not improved, or if less than one bucket of organic matter is used for an 11-square-foot (per 1 square meter) bed, cucumbers will depend on regular fertilization and will not grow without it.
Fertilizing “just in case” and “for greater yield” are principles that are not appropriate for cucumbers. This is not a plant that likes high levels of fertilizer. What is applied under the cucumber and on the leaves also affects the fruit. And the principle of a reasonable minimum fertilizer application is the most reliable.
Characteristics of Cucumber Fertilization
Cucumber is a crop that is responsive to organic matter. No mineral fertilizer can replace or compensate for the lack of organic matter in the soil. If mineral fertilizers are used, they should only be used in combination with organic fertilizers and in small amounts.
Cucumber needs nitrogen first at the beginning of the growing season, but it is not as predictable as other vegetables and is equally dependent on potassium.
During the fruiting season, it is not just phosphorus and potassium that are important for cucumbers, but mainly potassium, half of the nitrogen and calcium, followed by phosphorus and magnesium. And you should plan your fertilization accordingly.
How Many Times Should I Feed My Cucumbers in Early Summer?
Cucumbers should only be fertilized 3-4 times per season in the field and 3-5 times in the greenhouse. If the soil has been prepared at least minimally and there is a good supply of organic matter, then you only need to fertilize cucumbers 2 times in early summer.
- When the flowering period begins.
- When the first ripe fruits are set.
Fertilization should be started earlier only if cucumbers are sown and planted in fairly poor soil with low humus content. Still, remember that cucumbers are slow to assimilate nitrogen and phosphorus in the first 15 days and have difficulty assimilating potassium in the first 30 days. When planting seedlings, do not apply fertilizer earlier than 2-3 weeks after planting, and when sowing into the soil, wait until the 3 – 4 leaf stage. For poor soils, the maximum frequency of regular fertilization is every 14 days; the optimum frequency is at least every 3 weeks.
Emergency Fertilization for Cold-affected Cucumbers
If plants cannot be protected from unexpected frosts in time, the weather bumps unexpectedly, and young, fragile cucumbers in greenhouses or beds suffer from excessive cold, applying growth promoters is one way to try to save those bushes that are not completely affected.
If eggplants and peppers damaged by frost have to be thrown out, cucumbers can at least be revitalized. There are no guarantees, but it’s worth a try. The use of growth stimulants and bioinhibitors, combined with green manure irrigation, can sometimes help save bushes. Use stimulants as directed.
Organic Cucumber Fertilizer
The beauty of organic fertilizers is that you can choose almost any fertilizer – and use it correctly at any stage. If you don’t repeat the fertilizer every day, it won’t do any harm.
There is one option for cucumbers in the early flowering stage.
- Two to three weeks of infusion with chicken manure (1:20) or cow manure (1:10) at 0.26 gals (1 liter) per bush.
- infusion of nettle or other herbs (fill a bucket one-third full with chopped herbs collected before flowering, then add water and ferment the green manure under the lid for about 10 days, diluting it with 1:10 water) – 0.26 gals (1 liter) per clump.
- Yeast starter – 100 g of yeast and 50 g of sugar per 2.6 gals (10 l) of water, kept until active fermentation – 500 ml per clump.
In the fruiting stage, when the first ovaries are formed, use the best organic fertilizer you have, with the highest content of potassium, calcium, and magnesium.
The traditional way of fertilizing is to inject chicken or quail manure or cow manure (the ratio should be slightly increased by injecting 1.5 times more manure than at the beginning of flowering, such as chicken manure – the ratio should be changed from 1 to 20 to 1 to 15). Alternatively, fertilize with diluted compost – 0.52 gals (2 liters) of manure per 2.6 gals (10 liters) of water or any green manure. The application rate is the same – 0.26 gals (1 liter) per bush.
At this stage, it is also more appropriate to apply fertilizer with ash.
- Mix 500 g (or 2 cups) of ash with 2.6 gals (10 liters) of water.
- Stir regularly and soak for two days.
- Drain the finished infusion, leaving the sediment, and dilute it in 2.6 gals (10 liters) of water.
- Water the cucumbers with 500 ml of water per plant.
“Homemade organic fertilizers can be replaced at any stage with ready-made biological preparations such as Humisol, Stimovit, Humistar, Ecoplant, Orgavit, Organicum, etc., used according to the manufacturer’s instructions.
If fertilization is needed at an early stage – during active growth, 3 weeks after planting (in the 3rd-4th leaf stage of the ground plant) – a standard infusion of any organic fertilizer – cow manure, chicken manure, green manure – can be used, adding a yeast starter to the basic fertilizer to stimulate growth.
How to Use Mineral Fertilizers for Cucumbers?
If you do not follow the strict laws of organic vegetable production and prefer the proven macronutrient ratios of mineral fertilizers and the methods of conventional gardening, try to stick to the minimum rules of fertilization when using preparations – as a supplement to organic fertilizers. And be very careful to apply fertilizers at the stage of fruit formation.
For additional fertilization a few weeks after planting, use one formulation for every 2.6 gals (10 liters) of water and 10 shrubs to promote growth.
- 1 tablespoon of urea and 2 tablespoons of calcium superphosphate.
- 10 grams each of phosphate, potash, and nitrogen or 1 tablespoon of diammonium hydrogen phosphate.
- 10 grams of potassium chloride and ammonium nitrate and 20 grams of double calcium superphosphate.
For the first planned fertilization at the beginning of flowering, several fertilization programs can be used.
- 1 tablespoon of compound fertilizer (nitroamine, a compound mixture of urea, calcium superphosphate, and potassium sulfate).
- standard (manufacturer-specified) dose of cucumber compound fertilizer
- 40 grams of potassium sulfate, 0.3 grams of manganese sulfate, and 0.5 grams of boric acid.
If flowering is problematic and there are no ovaries, a higher dose of phosphorus application – 20 grams of potassium, 30 grams of nitrogen, and 40 grams of phosphorus – is acceptable. Additional foliar application: calcium superphosphate per 2.6 gals (10 l) / 25 g, boric acid (1 teaspoon), urea (2 tablespoons).
At the beginning of flowering, especially if the bush is weakened, you can also make a final application of growth promoter (e.g. sodium humate, 1 tablespoon in the basic fertilizer).
Second application – flowering and fruiting – using any of the formulas along with organic fertilizers (chicken manure, cow manure, green manure), dissolved in 2.6 gals (10 liters) of water.
- 1 tablespoon of any compound mixture or a standard batch of cucumber fertilizer according to the manufacturer’s instructions.
- 50 grams of potassium nitrate and 25-30 grams of urea.
- 1 teaspoon each of calcium superphosphate and potassium sulfate.
- 25 grams of potassium nitrate.
If there is a problem with ovulation, add 25 grams of calcium superphosphate or re-spray the leaves with urea, calcium superphosphate, and ash infusion for signs of nutrient deficiency.
General Rules for Feeding Cucumbers in Early Summer
Liquid fertilizer is not the only option, but it is preferred. Be sure to dissolve the fertilizer in warm, non-pungent water. While sprinkling is the best way to water soil-grown cucumbers, feed at the roots – so that the nutrients don’t soak through the leaves (especially if using mineral fertilizers).
With cucumbers (as with all other vegetables, in principle), fertilizer should only be applied when the soil is moist and well-watered.
Feeding times should be chosen wisely. Early morning and late afternoon are equally suitable, but it is easier to heat the water to the “right” temperature in the evening. There is also less risk. Cucumbers are fed on warm days, with nighttime temperatures above 50 °F (10°C), or nutrients will not be absorbed properly. If the weather is wet and the summer is cold, with temperatures often below 53 °F (12 °C), it is best to use foliar sprays instead of root feeding.