Planting the greenhouse – sowing calendar, growing vegetables yourself

Greenhouses come in different sizes, equipment and price ranges. Before you buy, you have to consider how big it has to be to cover your own needs and what everything has to be included, e.g. heating for the winter, automatic ventilation or irrigation, shading … So you have to decide whether you want want a cold house, warm house or temperature-controlled greenhouse. The smaller the available usable area, the more effectively it has to be used.

Furnishing

If you want to grow vegetables, you need some equipment in the greenhouse. The degree of equipment depends on the period of use, i.e. whether it is to be used all year round or only seasonally. The simpler and cheaper equipment is the one without heating and with manual ventilation and watering, but the automatic system offers many advantages.

• For year-round use, we recommend using glass or a very transparent material so that there is enough light available in winter. Glass must be shaded in summer. Alternatively, of course, you can also work with plant lamps in winter.
• 16 mm double-wall sheets made of plexiglass are often used. With good ventilation, they do not need to be shaded, they are heat-insulating, UV-permeable and non-yellowing for about 10 years. No glass can keep up with that.
• An insulated, frost-free, strip foundation is ideal. It keeps the heat in the soil and keeps voles off, which would also like to eat the delicious vegetable particles.
• In addition to the door, one or two windows should be available for ventilation. It is ideal if they work automatically. When the house gets too warm, the windows open. 10 percent of the outside area must be available as ventilation openings!
• A heat storage or heating device is required for year-round use. Depending on the location of the garden and the climate zone, a heating wire in the bed is sometimes sufficient.
• A fan can also help to keep the air out of the greenhouse.
• A work table is also required.
• Hanging shelves (shelves) create additional storage space, especially for small pots, which are usually available in quantities after pricking. Often you don’t know what to do with it. Several floors create space. It is important that there is enough light everywhere.
• Measuring and control devices for temperature or air humidity are favorable.

location

• Unheated greenhouses – north-south orientation
• Heated greenhouse for year-round use is east-west orientation better (use of light in the winter months)

Plant substrate – soil

The soil in a greenhouse is extremely stressed. That is why it has to be well cared for. So heavily used substrate takes time to regenerate. Correct fertilization is important in order not to leach out the earth. The best thing to do is to do without chemistry entirely. This is also better for anything edible that is to be harvested. You don’t want chemistry on your plate.

• The soil has to be loose, the soil has to be medium heavy and crumbly to fine crumbly so that the water can be well distributed.
• In addition, the soil must be fertile, i.e. it must be provided with sufficient nutrients.
• A 2-layer floor is ideal. Well-seasoned (2 years) horse manure comes in at the bottom and earth on top.
• Compost soil or manure to enrich the earth are also good.
• The ideal is to replace the floor every three years.

Sowing and planting

The first months of the year are mostly used for cultivation. Many plants are sown from January to March. In April the small seedlings are pricked out and put into the field a month later. If possible, leave the young plants in the greenhouse until there is no longer any threat of night frosts. With many plants there can be a space problem, the space is just limited. Therefore only prefer as much as can be accommodated.

Many types of vegetables are suitable for growing in the greenhouse, e.g. zucchini, cucumber, tomatoes, leeks or peppers. Lamb’s lettuce and spinach also grow even faster in it.
After the seedlings have been transplanted, there is space again in the greenhouse. This can now be used for the cultivation of vegetables, which often do not thrive so optimally outdoors, for example tomatoes, cucumbers and all kinds of lettuce. Cucumbers generally thrive better under glass, tomatoes are protected from moisture and become less ill, and lettuce is better protected from voracious snails.

Vegetable growing in the greenhouse all year round

If you have a greenhouse that can be heated all year round, you can grow vegetables in it almost around the clock. One problem in winter is the lack of light. However, you can make do with appropriate lights. There is always something to do. It is sown, pricked, moved and harvested in continuous use. What tastes good is always re-sown. It’s pretty simple in principle.

In the following sowing calendar you will find many important tips for growing vegetables during the year.

January

• Check older seeds for shelf life. To order something new.
• Seeds should be suitable for use in the greenhouse.
• From mid / late January onwards, you sow fast-growing, cold-tolerant salads and vegetables, i.e. lettuce, lamb’s lettuce, winter purslane, rocket, radish, radishes and onions
• Follow-up seeds can be sown every two to three weeks.
• If there is a risk of frost, cover the seeds with fleece!
• Floor heating under the growing bed is ideal. (Install underfloor heating cables 30 to 40 cm deep. On top of this, 5 cm of sand, then the earth). Usually only necessary from December to February.
• Don’t forget to ventilate whenever the weather permits.
• Pour carefully!

February

• Salads are sown (plucked lettuce, cut lettuce, rocket, lamb’s lettuce, winter purslane, salad onions).
• Always use early greenhouse varieties.
• Prick out the lettuce once and later plant it in the ground bed.
• The first types of vegetables are sown from the middle of the month, i.e. kohlrabi, spinach, chard and stick sauce. Pay attention to early varieties here too.
• Tomatoes can be sown at the end of February (early varieties)

March

• Sowing: lettuce lettuce, radish, stem butter, Swiss chard, broccoli, cauliflower, kohlrabi, fennel, celeriac, eggplant, paprika, pepperoni, tomatoes (late varieties) and pumpkins (all varieties)
• Depending on how far the seedlings are, they have to be pricked out.
• Start with preventive crop protection
• Hang up yellow boards so that the whitefly doesn’t stand a chance.
• The first vegetable plants are planted in the base beds of the greenhouse.
• Work in compost beforehand!

April

• First harvests – salads, rocket, spring onions, radishes, spinach and jam
• Don’t forget to water on sunny days. The pricked seedlings in particular dry out quickly in their small pots.
• If watering, then in the morning so that the plants can dry off before it is fresh again.
• Ventilate as often as possible.
• It is best to use an air circulator, 24 hours.
• Sowing: lettuce, lettuce, radicchio, spring onions, winter hedge onions, radishes, fennel, paprika, peppers, late tomatoes, runner beans, courgettes, cucumbers, pumpkins, melons and sweet corn
• If you like and have space, you can put a vine in a corner. The harvest takes place six weeks earlier than outdoors. Greenhouse size at least 2.5 x 3 meters. Good ventilation is important.

May

• Seasonwechsel
• The young plants can be planted outdoors. So you have plenty of space in the greenhouse again.
• hen yellow panels are no longer sufficient as plant protection, continue working with natural neem oil. Sprayings must be repeated in order to catch any later hatched pests.
• Everything that you want to harvest in summer is sown every 3 weeks
• Mainly sow salads, radishes and such vegetables again and again, but also prick out seedlings
• Plant tomatoes, melons and cucumbers in the greenhouse. Sweet corn, eggplant, and peppers also look good inside.
• Don’t forget to ventilate!
• Fertilize carefully!

June

• The water requirement in the greenhouse is increasing, it is almost twice as high as in the field.
• Fertilize!
• Ventilate regularly!
• Constant control for pests.
• The ideal time for organic plant strengtheners, e.g. horsetail tea. This can prevent powdery mildew
• Remove the lower tomato leaves (prevents late blight) and cover the ground with straw.
• Switch on the air circulator!
• Tomatoes and melons are regularly used
• Sowing: winter endives, lettuce, runner beans, radishes (summer varieties) and onions

July

• Harvest time
• Water vigorously, but never at lunchtime. It is ideal twice a day, in the morning and in the evening.
• Fertilize!
• Ventilate as often as possible and leave the air circulator switched on for 24 hours.
• Occasionally loosen the soil to reduce weeds and evaporation.
• Cucumbers are happy to have a slight shade. You can attach them with appropriate holders exactly above the plants.
• Check peppers and eggplants for aphids. The pests love them.
• Gray mold threatens, so ventilate a lot and leave the air circulator on!
• Continue to sow the usual types of vegetables and lettuce in rhythm, according to your wishes and taste.

August

• Water regularly.
• Slowly fertilize less.
• Prepare autumn crops
• Ventilate as much as you can. Close the door at night in cloudy weather – risk of gray mold from moisture. Air circulator in continuous operation!
• Chop the soil.
• Apply green manure to harvested areas.
• Watch out for spider mites, especially in warm and dry climates and especially with cucumbers.
• Yellow plates against whitefly.
• Remove newly appearing inflorescences from tomatoes. The fruits no longer ripen.
• Sowing: Swiss chard, spinach, lamb’s lettuce, lettuce, stick sauce and beetroot

September

• Big house cleaning
• Water more carefully when night temperatures drop
• Hardly fertilize
• Ventilate during the day. Leave the air circulator switched on
• Apply green manure to harvested areas – can remain on the areas in winter. Suitable are: alfalfa, bitter lupine, incarnate clover and phazelia
• Improve heavy soils with lime, add clay powder, eg bentonite, to light soils
• Sowing: lamb’s lettuce, lamb’s lettuce, winter lettuce, radishes, onions, winter purslane, stick jam, may beet, spinach, chard, fennel and parsley.

October

• Clear out summer crops now at the latest
• Clean the windows inside and out with a high-pressure cleaner. Dust that takes away light is removed.
• Pour only when necessary.
• Ventilate intensively. Ventilation and air circulation prevent fungal infections.
• Sows: French lamb, lamb’s lettuce, lettuce, wild rocket, rocket, winter purslane, spinach and radishes.
• The work becomes less.

November

• Little growth
• Harvest available vegetables and salads.
• In dry weather, ventilate, let air circulation.
• Connect heating, if necessary.

December

• rest time
• Possibly still harvest, e.g. lamb’s lettuce, Swiss chard, spinach, rocket or herbs
• Pouring very rarely
• Ventilate as often as possible if there is still a plant
• Sow in a heated greenhouse

Conclusion
A greenhouse is worth it. Nowadays you can buy anything at any time, but when you grow your own, you also know what you are eating. In addition, you only harvest ripe vegetables, which is noticeable in the taste. Of course, the cultivation is work and it takes time. If you have to force yourself to do it and don’t enjoy it, you shouldn’t. At times you have to do the right thing. You also have a lot of work to do during your vacation time. You have to put them on someone else’s eye or you stay at home. So everything needs to be considered. I keep dreaming about my greenhouse. At some point it will work out, I’m confident of that.