Which trays , containers, pots, pots , bases and under-dishes

Introduction: Why this article

I usually don't have to think long about what to write in the checklists. I look at the latest questions in my chat or mailbox and the inspiration flows in. Also on social media, especially on Fac Ebook , I also get a lot of pain in the eyes when I see some people proudly showing their seedlings. 8 tightly packed tomato plants with a hair-thin stem that cry and scream for space and light. You may have seen the photos too. I had already written an article Everything I know about pre-sowing . I talked about the principles of pre-sowing, why pre-sow, water and light, in broad terms what you can pre-sow. In this article I will go into more detail about what you grow, not only the pre-sowing but also the prickling out and the further cultivation on the terrace, for example.

What, where to sow and how?

PART 1 - Sowing in a tray

I sow in a tray to save space . Indeed, the pepper plant comes in a 12 liter pot on the terrace. But that does not mean that I will sow it in a 12 liter pot now. If I did, my house would be full. I also do not have room for 12 liter pots in my propagator or on the windowsill. In a tray I always sow in my own sowing and cutting soil mix of 3/4 coconut soil and 1/4 perlite . There is little nutrition in that mix, so when the plant has rooted in the cells of the tray , I have to prick it out to richer soil. The coconut soil does contain essential nutrients such as natural potassium, and phosphorus in moderate amounts and traces of nitrogen, calcium, magnesium, boron, chorine, iron, manganese, molydenum and zinc. coconut soil is therefore very suitable for sowing and is also a renewable source, peat, from which normal sowing soil is made, takes too long to grow back to be called a renewable source.

Always 1 root ball and only seedlings in a tray

A bit of a strange title but I will explain myself. Personally I choose to always transplant the plugs from 1 cell into one root ball. I will not tear them or pry the plants loose. Another principle is that I always use sowing and cutting soil in trays and prick out the seedlings as soon as they change from seedling to plant. With most plants that is when the second or third pair of leaves starts to grow. That is also the moment that the nutrition from the seed is used up and that the seedlings need extra nutrition.

How many seeds per tray ?

How many seeds you sow in a tray depends on which vegetable you sow but also on whether you want to make a selection. For peppers and paprika 's I sow 2 seeds per cell. That way I am almost certain to have a plant left per cell. What I do then is cut away one seedling with scissors.

How many seeds per cell?

Here it depends on how I want to plant the plants. I plant lettuce , a pepper plant or a courgette per 1 plant so I aim for 1 healthy plant per cell. In that case I also sow one seed or if the price of the seed type is low, I sow two to keep the best and cut away the weakest. I do not apply this trick with expensive F1 seeds . If I want to transplant several plants as a whole as I do with parsley, flowers, lettuce , rocket, ... then I sow several seeds in 1 cell. Never sow too close together in the cell, I rarely sow more than 6 seeds in 1 cell. Also experiment with different numbers. I now know from experience that when I plant 6 seeds of lettuce 10 cm apart in my winter greenhouse garden cupboard , that is much too close together. My lettuce Witte Dunsel was therefore too close together last winter and shot up quite quickly. Next time I will either sow 3 seeds with cell or plant my plug with 6 seeds at 20 cm. It is important that you understand the principle of number of seeds and planting distance.

Which tray for which vegetable?

The regular tray s

By regular trays I mean trays of 51cm by 30cm and a depth of +/- 5 cm. In our webshop they are made of hard or soft plastic and there are different diameters. I go from large to small.

trays with cells diameter +/- 5cm

In these trays I sow all the crops that I want to plant out in bunches (see above). I also sow the largest vegetable garden seeds in this tray . The seeds that are larger than half a centimeter, however, I sow in a different way, you will read about that later when I talk about pots. But beetroot , cucumber , gherkin, melon, ... still go in this tray . Large pumpkin seeds, on the other hand, do not. Sometimes you will catch me with a large tray (5 cm diameter) for smaller seeds , but that could also be due to laziness :)

trays with cells diameter +/- 4 cm

In trays with 4 cm holes I sow an intermediate size of seeds between 2 and 4 cm. spinach , lamb's lettuce , many types of flowers (if you don't want them in bunches in the larger trays ), tomatoes, aubergines , peppers , paprika 's, ... This tray is also ideal if you only want to buy 1 type, you can put a lot in it.

trays with cells of +/- 3 cm

This is for the small seeds that you want to sow individually, lettuce for example, also rapeseeds are often around 1mm. Remember that in the regular soft plastic trays you can grow 104 plants (3.5cm) in the same space of a 73 hole tray (diameter 4cm) where you can sow 73 plants. So definitely make a conscious choice in which trays you sow.

The deep root tray s

Some crops develop deep roots very quickly. When the roots reach the bottom, they can't go any further and they turn around looking for food and water, but the only thing they find is the bottom of your tray , and it's not really nutritious. The plants don't like that and they have a false start right from the start. Have you ever walked around in shoes that are too small for you? There are deep root trays for this, or trays for crops with deep roots. In our webshop you can find them with 60 holes of 4.8 cm x 4.8 cm in 3 depths: 9 cm, 12 cm and 15 cm. Here is an overview of what I use them for:

• 9cm: peas , beans, spring onion , onion, ...
• 12cm: leek , peas and this tray is also a good intermediate size if you only buy 1 tray to use for anything that has deep roots.
• 15 cm : broad beans

A base for the trays Because you shouldn't water every cell, because with 10 trays you would really go crazy, and also because plants drink from below, it is best to water in a container in which your trays stand, also called a base. I use these two models:

• tray Base 53 X 30 X 3.5cm with water drain at 1cm from the bottom - This base is perfectly suitable for all trays and you can lift the tray a little and water it in the base.
• Growing tray black thick plastic 56cm x 42cm x 9cm - Danish tray - This tray is made of thick hard plastic and you can also put your P7, P9, P11 or even your 5 liter pots in it later and move it easily. The tray base is just a little too sturdily for that and is only intended for trays .

PART 2 - Sowing in a seed tray

In our webshop you will also find different sizes of seed trays from small to large. You can work very quickly with them, faster than filling a lot of pots or a tray for example. Many vegetable gardeners sow in a seed tray like I sow in a tray . With a view to prickling out. But because the roots of the plants quickly get into a tangle and you have to try to unravel them, I never sow in a seed tray . What do I use seed trays for then?

For sowing sprouts

A lady from France grows sprouts on a large scale with our seed trays . She fills them to 0.5 cm from the edge with well-moistened sowing and cutting soil, she has made a board with a handle to press the soil and then scatters the seeds on the lightly pressed soil. The moisture from the evaporation of the soil is sufficient to make the seeds germinate. At the weekend she sells the trays at the local farmers market.

For sowing crops that grow quickly and transplant very easily

In the seed trays I also sow broadcast to prick out later. Crops that grow quickly and do not develop a large root system in that short period. Lettuce for example, with cabbages it might also work, tomatoes too (although I also use trays for my tomatoes). You should try it out and decide for yourself what you find easiest.

PART 3 - Transplanting young plants into pots

At certain times, you may want to transplant your young plants from a tray or seed tray into the open ground. It may still be too cold outside, but you can also choose to transplant your young plants into pots to protect them from birds, snails or other animals that are just as crazy about vegetables as we are. !! The purpose of the plants is to let them grow until the plants in the pot are well rooted. So make sure your timing is good in function of the planting out. Plants that stay in a pot for too long get 'rootbound' or root suffocation, plants that are not sufficiently rooted are difficult to plant out. With the Vegetable Garden Planner on this site you get the right dates for sowing, prickling out, planting out, fertilizing, ... definitely worth taking a look.

Which jars do I use?

I use three sizes of pots for prickling. The pots are not the place where the plants grow to maturity. We have used the trays and seed trays before to save space, on our windowsill, garden shed or propagator . Prickling pots give the plants the time, nutrition and space to grow further into young plants to plant out. Depending on the size of the plants and the length of time they have to stay in the prickling pot, I choose my pots. I use 3 types of prickling pots. I also place the crops that I grow in them into young plants to plant out:

P7 pots: 7 x 7 cm circumference and 8 cm deep

• Leafy vegetables: endive, celery, arugula, lettuce, spinach , lettuce and Swiss chard
• Cabbage crops: cauliflower , kale , broccoli , kohlrabi, red cabbage ,savoy cabbage, Brussels sprouts and white cabbage (press the potting soil well)
• Root vegetables: celeriac , turnip, seed onions and beetroot
• Fruit crops: cucamelon, cherry tomatoes, pot tomatoes and gherkins
• Herbs: basil, dill , chervil, coriander, mint, tarragon , cilantro, sage, rosemary and parsley

P9 pots : 9 x 9 cm circumference and 10 cm deep

• Fruit crops: eggplant , cucumber , corn , pepper , chilli and tomato
• Root vegetables: plant Shallot

P11 pots: 11 x 11 cm and 12 cm deep

• Fruit crops: pumpkin , zucchini, melon.
• Root vegetables: Garlic

PART 4 ​​- Which pots for which mature plant

If you choose to grow your vegetables, fruit or herbs completely in pots , you need the right pot that is big enough. You can grow almost anything in pots on your terrace, balcony or flat roof. A pot must contain the soil, nutrients and moisture that is needed for a plant to produce leaves, flowers and/or fruit. The roots of the plant must also have sufficient space. The pot must also provide sufficient counterweight for plants that grow in height or produce heavy fruits. Growing a courgette plant or tomatoes in a P7 pot will probably not be successful :) In addition to a lack of space for the roots, the plant will also starve to death and the pot will crack and fall over due to the weight. Maybe a nice competition for my YouTube channel. Plant a courgette seed in a P7 pot and wait for the pot to fall over. Whoever is closest wins a package of vegetable garden plants . What do you think? Some plants are small enough to sow several in one pot, others are too big and have to be planted one at a time in a pot. The depth of a pot should be at least 20 cm and you will have to water 2 to 3 times a week. A pot with a saucer or a Danish tray is very handy to water from below. Watering from above washes away your soil and is not so good. Below I present you my list of pot sizes per crop:

Leafy vegetables in pots

• lettuce : 5 liter pot (1 plant per pot)
• lettuce , Mesclun (Asian lettuce mix), Mizuna, Rocket, ... 5 liter pot (broadcast sowing)
• leek : Plant 18 leek plants in a 2.5 liter pot
• Celery: 8 liter pot (1 plant) or 40 liter pot (5 plants)
• spinach : 8 liter pot (3 plants per pot); 40 liter pot (plant 10 plants per pot)
• Chard / Swiss Chard: 8 litre pot (1 plant) or 40 litre pot (5 plants)
• Sorrel: Grow in a 2.5 litre pot (sow broadcast and thinly to 6 to 8 cm)

Legumes in pots

• peas : in a 40 liter pot 5 cm between the peas , provide a climbing frame for the tall varieties.
• Bush beans ( dry beans , sbij beans , princess beans ): 5 liter pot (2 plants per pot)
• Princess beans: 12 liter pot (2 plants per pot)

Cabbage crops in pots

• cauliflower : 12 liter pot (1 plant in 1 pot) or 40 liter pot (3 plants)
• kale :