October 4, 2002
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Gardening 101 Pests & Disease Propagation Seeds Spring

Seed Starting – Germination

Guest post by Beate Schwirtlich

What Happens When A Seed Germinates?

The whole purpose of starting seeds indoors is to cheat winter a little.

Ironically, even as we cheat nature, we must imitate her. Light, soil, water, air, and a basic understanding of the process of germination are all you need. Once you know the simple things a seed requires, starting them indoors won’t seem half as complicated.

Seeds are their own energy source, a plant in embryo form. They store energy in a form that is released and used only when water, oxygen, soil, and a close-to-ideal temperature are a part of their surroundings.

Until then, they remain dormant. Germination inhibitors are part of the make-up of every seed. They actually prevent a seed from germinating until its chances of survival are good. Usually chemical in nature (five per cent of seeds are simply waterproof, dormant until their seed coat cracks), germination inhibitors put a seed into dormancy. Without these, a tomato seed, for example, would spout right inside the fruit of the plant that formed it, where there is moisture and warmth, good conditions for germination. Inhibitors give a seed time to travel away from the parent plant, and allow it to overwinter, or be stored, giving that seed the best possible chance to reproduce successfully and to spread. Germination inhibitors ‘wear off’ over time, allowing a seed to sprout the next year.

The seed coat or outside of a seed protects it during dormancy. Hidden inside that coat is the radicle or beginning of a root, the hypocotyl or beginning of a shoot, either one or two seed leaves or cotyledons (the seed’s food supply), and the epicotyl, which will become the first true leaves. The seeds of some plants have a second food supply, called the endosperm. Plants with one cotyledon are called monocots. Those with two are dicots.

Spring like conditions soil that’s wet and beginning to warm up, and longer days and stronger sunlight signal the seed to break dormancy. Light triggers germination of many small seeds, while other seeds germinate best in darkness. Some seeds prefer warm temperatures, others cold. Such differences are a reflection of biodiversity. Simply, plants native to areas with warm conditions produce seeds that germinate best in warm soil, while those native to cold places prefer cool soil.

Know what conditions your seeds naturally prefer, and try to emulate them.

Water does two things to a seed. First, it activates enzymes that stimulate the release of food energy stored during dormancy. Second, it splits the tough seed coat open so that oxygen gets in. Energy stored in the cotyledon ‘burns’ and is used only in the presence of oxygen, powering the seedling’s cells as they begin to divide and grow. This process is called respiration.

Soil holds the water and air that a seed needs to respirate. Too much water drives out air pockets in soil. Don’t over-water. Without air, seeds can’t use their stored energy through respiration. Never let seeded soil dry out. Without water, seeds can’t use their stored energy.
This stored energy only lasts so long. That’s why a sprouting seed works so hard to break the soil and unfold into the light quickly. It’s also the reason that germination of many seeds is triggered by light. If a small seed germinated in a moist but dark environment, it might run out of energy before ever reaching the soil surface. But if a seed needs light, it won’t germinate until it’s close to the soil surface. That way, it has a chance to survive. But before a seed begins to grow up, it grows down, anchoring itself with a root, the first life to emerge from the seed coat. The root allows the spout to begin to absorb water and food from the soil.

A seed can only store so much energy. That‘s why smaller seeds must be planted shallower, larger seeds deeper. Little seeds planted too deep will exhaust themselves and die underground. Large seeds can easily dry up if planted too shallow. Really small seeds should just be pressed onto the soil surface.

Next, the shoot begins to grow, splitting the seed coat even more. Soon, the growing shoot pushes the seed leave(s) above the soil. They unfold, sometimes still wearing their dried up seed coat on their tips. As the root continues to grow, a bud will appear between the seed leave(s). From this, the first two true leaves will grow, enabling the plant to begin to photosynthesis, the production of energy using light.

Lacking light, seedlings will compensate by shooting up towards the light source and becoming ‘leggy’ and weak. Provide lots of light twelve hours a day. Use a south-facing windowsill, or good artificial lighting.

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October 4, 2002
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Propagation Seeds Spring

A Quick and Easy Germination Test

Guest post by Arzeena Hamir

If the holidays have pretty much wiped you out, here is a simple activity that will not only save you money but will help organize your garden for the upcoming year.

Like many gardeners, my stash of seeds has accumulated over the years to the extent that I often forget what varieties I’ve bought. Some of these seed packets date back several years so before I take a chance, basing my whole crop of sweet corn on that package from 1997, I do a germination test. A test can be done on as few as 5 seeds but a more accurate prediction of germination percentage requires at least 20 seeds.

I use a very low-tech method of germinating seed: damp paper towels and plastic bags. Moisten one towel and arrange your seed on the sheet. If the seed is large (peas, beans, corn), apply another moist towel on top and roll the 2 sheets together into a tube. If the seed is small, the sheet can be folded over and then rolled onto itself. Once rolled, the paper towel should be placed inside a plastic bag or Ziploc to keep it from drying out. Finally, place the plastic bag in a warm spot (on top of the VCR, in the kitchen, on top of the fridge).

Before rolling the sheets, make sure the seeds are not too close to each other. Seeds that don’t germinate can begin to mould and this mould will infect nearby seeds if they’re too close or touching.

After about 2 days, check the paper towel at least once a day to see if the seeds have started to germinate. If the towels have started to dry out, re-moisten them with a couple of drops of water. Most seeds will germinate within 5 days at room temperature.

The majority of vegetable seeds will keep for at least 3 years if they’ve been kept cool & dry. The types of seed that don’t store well include sweet corn, parsnips, Swiss chard, spinach, and members of the Allium family (onions, leeks, scallions, chives).

The percentage of seed that do germinate in the towel will give you a pretty good idea of how they’ll do in the garden. If only 50% of the seeds germinated in the towel, you may want to consider planting the seed closer together to compensate for the seeds that don’t emerge. Alternatively, you may want to peruse your favourite seed catalogue and replace that seed package.

Finally, being the frugal gardener that I am, I hate to see a germinated seed go to waste. I pot-up whatever I can and keep them growing under lights. In the case of root crops, I plant the pre-germinated seed directly in the garden. I get a much better stand by doing this, especially if the soil is still slightly cold and would have caused un-germinated seed to rot.

Arzeena Hamir is an agronomist and garden writer based in Vancouver, BC. She has worked in the organic gardening industry for 8 years as a consultant and trainer. When she’s not planting peas or harvesting zucchini, she runs Terra Viva Organics.

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June 4, 2002
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Flowers Gardening 101 Propagation Seeds Summer

Summer Seeds

It may be summer, but it’s not too late to sow some seeds. Here’s a list of perennials that can be started from seed in July and August.

July Perennials

  • Astilbe
  • Bellis Perennis
  • Campanula
  • Gailardia
  • Foxglove
  • Gypsophila
  • Holllyhock
  • Linum
  • Lunaria
  • Lupin
  • Myosotis
  • Pansy
  • Poppy
  • Pyrethrum
  • Primula
  • Sweet William

August Perennials

  • Arabis
  • Armeria
  • Astilbe
  • Bellis Perennis
  • Campanula
  • Candytuft
  • Dephinius
  • Gaillardia
  • Lychnis
  • Myosotis
  • Plytycodon
  • Primula
  • Viola
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May 30, 2001
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Fruit Projects Propagation

Save Your Plant – Pineapple Top

If you happen to have a pineapple on hand to eat, (and they are abundant and cheap during the late spring and summer months), then why not take a few minutes and grow your own pineapple plant from the discarded top?

It seems nearly mythological that anyone can grow a tropical fruit such as pineapple in his or her own home. But as long as you have a sunny window and a moderate indoor climate you can grow your own. Don’t expect a large harvest. Each plant produces one fruit and yours will never grow to the size of a full grown Hawaiian-farmed plant, unless you do live in a tropical climate.

Pineapple
Ananas comosus

  • High in vitamin C
  • First commercially grown in Hawaii
  • Anana means “excellent fruit”

A fruit that is green and fresh picked is best. But, since it is unlikely that you would want to eat such a fruit, try to find one that is ripe but not overripe. Test for ripeness by gently pulling on a leaf. If it pops out with ease, the fruit is overripe.

At home, slice the crown (that’s the leafy top part) off the fruit. Be sure to remove all the flesh. If you don’t remove this material it may rot in the soil. Carefully slice small, horizontal sections from the crown until you see root buds that appear as small dots or circles on the cut surface. [See pic] The root buds are where the roots will eventually emerge and exposing them will facilitate quicker root formation. My pineapple top already had small roots formed as well. Strip off about an inch of lower leaves from the base to provide a stem for planting in the soil. Then set the plant top aside for a minimum of seven days in a dry place, out of full sun. The cut end must be allowed to heal and dry before planting, otherwise the plant will rot in the soil.
Although the pineapple plant is a Bromeliad, it is not an air plant and requires a soil bed. Regular potting soil is sufficient, but I like to add a small amount of sand to the mixture. Pineapple plants require soil that is barely moist, not wet. I suggest using a clay or terracotta pot that breathes, to help avoid over-watering. Water your plant once a week, spraying the leaves in addition to wetting the soil. Fertilize four to six times a year.

The pineapple plant requires a lot of light. Keep yours in a sunny window throughout the winter, in a location that is protected from drafts and cold temperatures. In summer place your plant outside in a sunny location, being careful to allow the plant to adjust to more direct light by placing it in an area with partial sun for a few days first. If you don’t take this precaution your plant will be burned. Do not leave your plant out during freezing weather. Pineapple plants should never be subjected to temperatures lower then 60 degrees F ( 16 C ).

Getting a pineapple to bear fruit is harder than growing one. Once your plant is approximately 25-30 inches tall it will flower and produce fruit on its own. But how many people have the space for a 30 inch plus spiky plant? It will take at least two years to grow a plant of that size in a temperate climate.
Luckily, there is a way to force your plant to flower and bear fruit when it is half that size.

Wait until the winter season when the days are shorter and the nights cooler. Pineapple plants normally begin to produce fruit during this time. Place the entire plant, including the pot, into a plastic bag with some ripe apples. As apples rot, they emit Ethylene gas which tricks the plant into forming a flower instead of producing new leaves. Keep the plant in the bag with the apples for approximately 2 weeks or so. Place the plant back in a sunny window and wait for a flower spike to form in the center of the plant.

After several months the flower will dry out and the pineapple will form at the top end of the stem. Wait until the fruit turns a golden yellow colour before picking. After harvesting the fruit you may notice new shoots left on the plant. These can be removed and planted in the same method as the original mother plant. You can also grow another plant from the crown of the harvested fruit, leaving you with several, new, free plants.

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