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Plan your new greenhouse calendar
A year has soon passed, and what a year. The climate crises have been replaced with a war in Europe and an energy crisis. The food prices have gone up, and we who love greenhouses, love greenhouses even more. The greenhouse can contribute to stable self-sufficiency all year around.
In a short time, we welcome 2023. It is time to plan next year’s cultivation in the greenhouse. I always start by looking through my greenhouse calendar and see what I have accomplished through the year.
Your greenhouse calendar.
What worked? What needs to be changed? Use about 10 mins to write this down.
Were you happy with the number of plants? Did you have enough tomato plants? Did u miss any sorts? Should you have grown that aubergine as you said you would? Was there to few or to many spicy chilis? You probably have all sorts of different questions you can ask yourself.
Spirekassens thoughts on 2022 and 2023
We have two greenhouses. And older orangery and a new Juliana greenhouse. In 2022 we discovered that 30 to 40 tomato plants were too much. We avoided blossom rot by having a healthy climate in our greenhouse and by combining rainwater and boring water. Aubergines are really fun to grow and well suited to grow in pots.
Our Juliana
- In the start of spring, we started germinating our flowers.
- The past year, we did not have enough pepper and chilli plants. Next year, we want more!
- On our list is also to grow more aubergines.
- We want to grow dwarf tomatoes and tomatoes grown in hanging pots.
- Our new Juliana greenhouse is lovely, but too hot. We need shade curtains.
- More mobile beds, to change our interior if we want to.
- But we will keep our excellent table and the 10 workstations for our 2023 greenhouse.
Our old orangery
- From march, we welcome spring with a big bed of tulips and daffodils.
- Fewer tomato plants during the summer.
- More flowers. For example, Celosia argentea, that thrives in the greenhouse.
- Earlier prepping for winter cultivation.
- More shadow curtains.
It is very important to evaluate the past year. But do it BEFORE you start buying new seeds, new gear for growing and equipment for the greenhouse. Think about what can be reused. It is often common sense.
Tips and guidelines
A tomato or cucumber per square kilometre is huge.
An example, if you have a 10 km2 greenhouse, you should not have more than 10 tomato plants of normal size, in your greenhouse.
It is a good, but boring rule, to the plant enthusiast. However, it is a great guideline in order to ensure a healthy climate for your greenhouse. To many plants and you will have a hard time keeping your greenhouse healthy. A crowded greenhouse is harder to air out and fungal diseases are more likely to occur. This rule will help you remember not to plant to many plants.

Om Spirekassen
Christine Wiemann is a greenhouse grower and an agricultural technician and owner of the seed company Spirekassen. Christine is an author of several books about lifestyle, garden life and plant cultivation. Today she writes blogs and shares her knowledge and passion for greenhouses. Christine is a greenhouse expert and an ambassador for Juliana Drivhuse.
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