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how many cilantro seeds per pot

How Many Seeds to Plant Per Hole, Pot, or Cell?

I recently got an email from Sally with a familiar question. It’s the same exact question that I had when I was a beginner gardener and wondered how to start seeds:

“I’m sure this is a silly question, but I always see it recommended to plant more than one seed per hole. But why? I just got a seed starting kit with some seeds and want to make sure I’m using them efficiently. Can you help me out?”

It’s a great question, Sally! Understanding the answer to this question will improve your understanding of gardening and seed starting in general, because the answer hinges on an important concept: seed germination.

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Video Guide

Answer One: Seed Germination Rates

Not all seeds are created equal. Some plant species have higher germination rates than others. Even within a single plant type, some of the seeds are older than others, causing the germination rate to go down.

Imagine you’re growing arugula and the average germination rate is 90%. If you plant a 72 plant starter tray with one arugula seed per insert, you can expect only 65 of those plant inserts to actually germinate (72 x 90%).

Now imagine you plant three arugula seeds per insert. Each of these seeds has a 10% chance of failing, so the probability of them all failing is 10% x 10% x 10% = 0.1%. This means that you are 99.9% likely to have the seeds in that cell germinate. So in a tray of 72 inserts, it would be extremely unlikely you would have any seeds not germinate — barring other factors that affect seed germination.

In short: Planting more seeds per hole increases chance you have perfect germination rates.

Answer Two: Seedling Selection

Just like not all seeds are created equal from a germination standpoint, not all seeds germinate equally. Sometimes you have a seed that shoots off like a rocket and becomes too leggy. If this was the only seed in your insert, you’d be forced to use it.

By planting 2-3 seeds per cell, you allow yourself to luxury of choosing the seedlings that look the strongest. All you have to do is determine which one you like the most, then snip off the other seedlings to kill them.

Exceptions to The Rule

Like most things in gardening, there are always exceptions to this rule of 2-3 seeds per hole.

If you’re planting large seeds like cucumbers, melons, or pumpkins, you should only use one seed per hole. However, you can still plant seeds close together and then thin them out once they’ve established themselves. You just want to avoid crowding these large seeds together so you don’t mess up the germination process.

If you’re growing certain herbs (cilantro, dill, basil), you can get away with planting multiple seeds per hole and leaving them all there as they germinate. These plants can handle being planted right next to each other and basically become one larger, bushier plant.

Now that you know how many seeds to plant per pot, you have a deeper understanding of seed germination in general. For more on seed starting, please check out the simple seed starting for hydroponics guide.

A common question I get by email is, "How many seeds should I plant in each hole or cell?". It's a good question with a great answer — read on to find out!

How to Grow Coriander

Variety is important!

Coriander (Cilantro) can be either grown for its leaves or for its seeds. Varieties have been bred to be better at producing one or the other so the variety you choose is important. A seed variety will produce seed quicker than a leaf variety but once a plant ‘runs to seed’ it will stop leaf production. If you want coriander leaves for your cooking this means you will have a shorter picking time. All varieties will eventually produce seed but the leaf varieties will hold off for longer.

In our opinion coriander ‘Calypso’ or ‘Leisure’ are the best for leaf production as it has an excellent ‘cut and come again’ habit while ‘Santo’ will produce larger flower heads and run to seed more quickly. You do not need to choose these varieties but make sure to check if the seeds you are using are ‘seed’ or ‘leaf’ varieties.

How to Grow Coriander

Coriander enjoys a sunny position but appreciates a little shade during the hottest part of the day. Plants will run to seed more quickly if stressed by hot weather so this is important for leaf varieties.

Sowing Coriander

Coriander is sown from late March until early September. To achieve a constant supply of leaves through the Summer sow small amounts every 3 weeks. The best months for leaf production are late spring and Autumn. Coriander is will grow best sown directly rather than grown in seed trays and transplanting. This is because transplanting disturbance will also cause then to run to seed.

Sow directly into well drained, fertile soil. If your soil needs to be improved add good garden compost or well rotted manure. Rake into the surface of the soil to remove any large lumps or stones leaving a fine and even tilth. Seeds are best sown in groups of 5 spaced 20cm between rows and 20cm between plants.

You can also grow coriander successfully in pots or trays filled with a good multipurpose compost. Coriander plants have deep tap roots so pots need to be at least 25cm deep. Scatter seeds on the surface of the compost and cover, watering well. In a pot of 25cm diameter you can sow approx 5 seeds per pot.

Caring for Coriander

Germination of coriander takes up to 3 weeks. Thin young plants to 20cm apart to allow them to grow to their full size. Water them in dry periods and ensure the soil never dries out. If flowers develop remove them immediately – this ensures the plants focus their energy on growing new leaves. Re-sow coriander every three weeks to ensure you have a continual supply during the summer. It is not normally necessary to feed coriander if the soil is well nourished. However is the plants appear to be suffering give them a liquid organic feed to perk them up.

Harvesting Coriander

Harvest the leaves when the plant is big and robust enough to cope. Pluck or cut each leaf off the stem or snip whole stems if necessary. Both the leaves and the stalks can be used.

If you are growing coriander for its seeds, wait until the flowers have died off before harvesting. Cut the stems and place the heads of the coriander in a paper bag, with the stems slicking out. Tie the stems and the bag together in a bunch and hang upside down in a cool, dry place. Wait for three weeks and then shake the bag. The dry seeds will fall out from the flowers and be ready in the bottom of the bag. Keep them in a dry place and re-sow the following spring.

Coriander is a versatile herb popular in Asian cooking including curries, Chinese and Thai dishes. Both the seeds and the leaves of the plant can be used, and offer two distinct flavours. The seeds have a slight lemony flavour; they are often ground and used as a spice. The leaves (also known as cilantro) have a slightly bitter taste and can be chopped up and added to dishes and breads or used as a garnish. Coriander is a tasty herb to grow, both for its leaves and seeds. If you re-sow seeds every three weeks you can have lush coriander leaves throughout the summer to add to salads and Asian dishes.

How to grow your own coriander herbs a comprehensive guide. Used alot in asian cuisine, Coriander is a very useful herb to have in the herb garden