Peat based (or a peat alternative) type compost is ideal.

Now this is the time to decide if you want to sow your seeds in trays, inserts or pots.

It is also time to calculate how many trays, inserts or pots you will need to sow the number of seeds you are going to sow.

As a rule of thumb, you can easily sow up to 50 petunia seeds in a 75mm (3 inch)pot. Or up to 100 petunia seeds in a half size seed tray. 200 in a full size seed tray and any combinations in between.

Sieve enough compost, on to your potting bench, or potting tidy/caddy, to fill all your trays or pots.

Don't discard the sieved out lumps and bits. These can be used in the bottom of larger patio pots when planting them up with your own home grown plants. (Save the lumps and bits in an old compost bag until needed).

Fill the seed tray/s or pot/s with compost to about 5mm below the rim (this does not need to be exact - about 5mm will do).

Lift the tray or pot to a height of about 15cm (6 inches) and gently tap it on the bench. Do this about three times. This will settle the compost into the tray or pot to about the correct level.

The compost should now be about 10mm (1/2 inch) from the top of the tray or pot. This does not have to be exact so don't worry if it is a couple of mm higher or lower. It will make no difference to the end result.

Take your correct size tamper and gently level the surface of the compost. DON'T push the tamper with any force. All we want to do here is level off the surface of the compost, NOT compact it.

*This gives an ideal surface to sow the seed on. *(Doing this correctly will increase your propagation success rate)

That's it. You have now successfully filled your first tray or pot with compost.

Now Fill the rest of your trays or pots in the same way.

This is the fun part, sowing the seeds.

Petunia seeds are very fine, there are over 100 seeds in the picture on the left.

To count out the number of seeds you want is not really practical.

So this is where practice and experience helps.

The easiest way to sow petunia seeds is to take a pinch between your thumb and forefinger and gently and lightly sprinkle the seeds over the surface of the compost. Take your time doing this, have patience. Get this right and you will be well rewarded with fine healthy seedlings.

The idea is to get the seeds spread out across the compost and not bunched up in patches.

The problem is once you have sprinkled the seed onto the compost it is difficult, if not impossible to see them.

So, you can practice sowing seeds quiet easily without using the seeds.

Take a pinch of sand between your thumb and forefinger and sprinkle it over the surface of the compost. (Use dry horticultural sand). The sand will show up on the compost, this gives a good idea of how well you will spread the seeds.

Mix the sand into the compost with your finger, dibber or similar, until it has disappeared and try again. The sand will not harm the seeds or the emerging seedlings, in fact it will assist with opening up the compost and provide additional drainage.

Do this a few times until you are happy with the results.

Now do it for real with the seeds.

There you go see how easy it is?

All that is needed now is to cover the seeds with a very light "dusting" of sieved compost. Just enough to cover the seeds and no more.

When you have sown all your seeds don't forget to label them with plant name and date of sowing.

Watering

Water your trays or pots with great care.

With your mist sprayer, set at it's finest spray, filled with tepid water and held at about 100mm (4 inch) from the pot or tray, lightly spray the surface of the compost. Don't get to close, or overdo it here, you will disturb the seeds which is exactly what you don't want to do!

The idea is to settle the surface of the compost with the fine mist from your sprayer. This prevents the seeds being disturbed.

Now fill a container, large enough to put the tray or pot in, with tepid water *(preferably water that has been standing in a warm place for about twenty-four hours) and definitely NOT rainwater, use good old tap water!

Stand the tray or pot in the container of water and leave it until you see the surface just becoming moist.

This usually happens fairly quickly so don't be tempted to go off and do something else.

*Do not overdo the watering process, you don't want the compost saturated, or your seeds may rot and not germinate.

*(By doing this correctly you will greatly increase your chance of success).

Germination

Cover your trays or pots with glass or clear plastic (or preferably, for ease of use, place in a propagator - unheated will do).

Keep your tray or pot in the light, (not direct sunlight) and maintain a temperature of 20C to 25C (68F to 77F).

After Germination

When your seeds have germinated and are large enough to handle transplant them into seed trays.

Be very careful handling the seedlings. Do not handle them by their stems as this will cause irreversible damage resulting in the seedling collapsing.

Handle the seedlings very gently and only by their leaves.

Tease the seedlings roots out with great care ensuring not too many roots are damaged. Time and care taken hear will really pay dividends giving your seedlings the best possible chance of growing on successfully.

Plant them in your seed trays about 5cm (2in) apart in a good quality potting compost. A sieved peat based or peat alternative compost will be fine.

When you have transplanted all your seedlings don't forget to label them with plant name, sowing date and transplanting date.

Water your trays or pots with great care.

Fill a container, that is large enough to put your seed tray in, with tepid water *(preferably water that has been standing in a warm place for about twenty-four hours) and definitely NOT rainwater, use good old tap water!

Stand the tray of seedlings in the container of water and leave it until you see the surface just becoming moist.

This usually happens fairly quickly so don't think about going of and doing something else.

*Do not overdo the watering process, you don't want the compost saturated, or your seedlings will rot and die.

*(By doing this correctly you will greatly increase your chance of success).

Keep the transplanted seedlings in good light (not direct sunlight) until they are large enough to be harden off.

Nice healthy petunias grown from seed in a half size seed tray. This is an ideal way of growing plants such as petunia from seed.
These seedlings are just the right size for transplanting into seed trays or single pots.

Grown in seed trays is a highly recommended way of growing plants such as petunia from seed.
Remember this when you come to sow your petunia seeds. It will increase your chance of success!

Aftercare

Plants should be gradually be hardened off by placing them outside, in a sheltered position, during the day.

A cold frame with the lid open is ideal for this. If it is very cold during the day close the lid, but watch out for excess condensation.

If there is excess condensation prop the cold frame lid open slightly until the condensation disappears.

Bring them in at night to avoid severe frosts.

When they are ready for planting out, make sure it is after the last frosts.

If you have any queries or comments please feel free to

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