Sowing, germination and growing guide

I though it is about time to summarize all we have learned so far about sowing seeds, ensuring high germination efficiency and nurturing plants. It is difficult to find one source online with all the necessary basic as well as more detailed information. We had to look at multiple information sources and learn over the years. Now we would like to share our experiences:

 

Buying seeds

For ideas on where to buy seeds I have compiled a summary of websites we have ordered from here. This will give you a starting point for your seed buying.

Seedling soil

You can buy special seed compost in garden centers, but just some standard fine soil does the job. Just as long as it is not too rough with bits of wood chip and bark in it.

Soaking seeds before sowing

Do look carefully at the instructions on seed packets. Some suggest to soak certain seeds in water over night before sowing them into the soil. This is usually the case for seeds with a harder coating (e.g. bitter gourd seeds).

Sowing containers

It makes life a lot easier for you later if you sow your seeds in biodegradable pots. These can then be easily placed directly into the next bigger pots, without having to disturb the plants and their roots. You can buy these in garden centers, or you can make your own from newspaper. We found that making your own, straight sided pots from newspaper is better, since then you can place several pots next to each other without any air gaps in between. This facilitates moisture retention and therefore prevents little pots from drying out too quickly. The biodegradable pots we find in garden centers here don’t have straight sides, which means there are a lot of air gaps in between if you have a whole tray of them lined up. 

It’s just a matter of making it more simple for you to take care of the little seedlings. This year, with Alex’s own made newspaper pots we have had less trouble with drying out seed pots. 

Germination temperatures

Once you have sown the seeds (do check on the seed packets or online how deep to sow different seeds) you should also make sure you check germination temperature requirements for different seeds. If you place different seeds at the right temperature they will just germinate more quickly and it will increase  germination efficiency too. 

We have now got ourselves a small, heated seed incubator with a soil temperature probe. We use this incubator for seeds which require higher germination temperatures. It works well.

Moisture

Seeds grown in the heated seed incubator are easier to keep moist. The seed incubator has a lid with vents which can be closed or open. We mist the seed pots each day with a little spray water can and keep the air vents mostly closed. This seems to generate good moisture levels. If we are away for a few days at a time we place a bowl of water next to the seedlings in the seed incubator. This prevents the seeds from drying out while we aren’t home.

Alternatively, if you do not have a seed incubator, you can mist the pots with water and then simply cover them lightly with cling film. This also works, but requires more watering to keep the pots moist.

Green flies

Once your seeds have germinated they spend rather a long time growing indoors because temperatures outdoors are too cold. We often struggle with green flies settling on the underside of the leaves or particularly on new shoots coming up. If you leave green flies unattended they really go out of control and ruin your seedlings. We have developed several strategies for combating green flies:

  • check your seedlings daily and squash any green flies with your fingers. Make sure to check on the underside of leaves -green flies like to hide there! Do the squashing gently so as not to damage new shoots.
  • Mist the plants with water containing a few drops of detergent (dish washing soap or hand soap – 1-2 small drops are totally sufficient). Green flies do not like alkaline conditions.
  • Also, once your plants get bigger leave enough space in between pots. Good aeration helps prevent green flies and other pests.

Watering

We find the most challenging aspect of taking care of young seedlings is the watering. Whatever you do, you do not want to over water them. The difficulty here is that you may not notice you have over watered before it is too late. Over watering prevents roots from taking up nutrients from the soil as well as getting air (you drown the roots). It is therefore better to rather under water than over water. We usually water well and then leave the pots to nearly dry out before watering again. You definitely do not need to water every day. Just feel the top of the soil every so often. If it is damp, do not water more.

Rescuing over watered plants

I have had to rescue tomato plants from over watering before! They drooped completely. People often take this as a sign that the plants need more water, but they need the opposite! When it happened to some of our plants I just did not want to lose them. They were still quite small so I could easily take them out of the soil and gently pat the roots dry with some kitchen towels. I then placed the plants into new pots with completely dry soil and left them to recover for a few days. They perked up and continued growing. 

Acclimatization

Once night time temperatures consistently stay above 10 degrees C one can technically put seedlings outside.  We like to be cautious though and keep them in their temporary smaller pots for a while longer so we can take them inside if temperatures drop again. We also recommend to take plants out during some sunny warm days but take them back inside for the nights the first few days. This way the plants get used to the change slowly. Once they have acclimatized and you are absolutely certain temperatures won’t drop too low you can place them in their permanent positions.

Sun burn protection

Even though plants like sun their leaves can get sun burned when they are still young and not used to it. If the sun shines directly on them, protect them initially during acclimatization.

Wind protection

Wind is important for promoting strength in plants. Exposure to some wind makes the plant stems grow more robust. Still, in stronger winds branches can break. You can stabilize taller plants with poles/stakes. Supporting plants as they grow is very important. The taller they get, the more likely they will break in the wind or even just because of the sheer weight of fruits they carry. We like to now use metal spiral poles. It is easy to guide plants up the centre of spiral poles, providing them with stability. As well as pushing the poles into the ground at the base of the plants, we also make use of our balcony roof to attach the poles at the top. This prevents too much movement of the poles in the wind.

If branches do get damaged, don’t worry.  You can fix broken branches in most cases. After a storm we once noticed that one large branch on our tomato plant had bent and kinked.  We didn’t want to remove it, as it was a branch with a large truss of tomatoes. Since the branch wasn’t completely broken, we supported it with two wooden sticks and some plant tape (a bit like a splint!). Plants are very good at recovering from damage. Tomato plants are incredible: as long as nutrients can still travel through the damage into the branch all you need to do is support the broken branch and it will continue to grow and produce fruits. 

Pinching out plant tops and side shoots

Once plants have reached the desired height it is important to pinch off their tops. This promotes plants to put in energy to produce fruit, rather than keep growing taller and taller. Depending on what plant you are growing it is also important to limit the number of side branches. For tomato plants we usually try to pinch off the top once the plants have made 5 side branches. Then we also continue to pinch off any additional side branches which start forming after that. Tomato plants produce side shoots very rapidly in side branch-main stem junctions. It is very easy for this to get out of control. You can just leave them to grow, but the plant will not put in as much energy into fruit production. Additionally, if a single plant bears too many fruits it will not have enough energy to ripen them all well. This can result in many less flavoursome fruit than if you keep the plant more controlled.

Pinching out first flowers

This may seem a little weird, but it is good to pinch off the first flower buds on vegetable plants. If plants start to put energy into flowering and fruit production too early they will not become very strong and high yielding in the long run.

Plant specific care

Different plants will of course need slightly different care. More specific details on different plants can be found under the different plant categories here.

 

 

 

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