How Long Does it Take for a Seed to Germinate?

Updated/Fact-Chacked on March 9, 2022 by John

The seed you see is in a dormant or sleeping state. It is waiting for the right conditions to awaken it.  If you want to make a plant out of it, you need to provide the right conditions. This article explores, how long does it take for a seed to germinate?

This guide will also cover factors that affect germination and sprouting and how to provide the right conditions for germination. Before getting into how long different seeds take to germinate, let’s first define germination. 

What is Germination?

Germination is the process a seed undergoes to come out of its dormancy state to develop into a plant.  Germination starts with the seed drawing water inside. It swells and produces various enzymes. This triggers a host of metabolic activities in the seed. Eventually, the endosperm breaks and roots emerge from the seed.

Seed Germination Requirements

Germination requirements are divided into external and internal factors. The external factors include 

  • water, 
  • oxygen levels, 
  • temperature
  • soil structure
  • and light or darkness

And the internal factors include age, auxins, food, dormancy, and viability.

The optimum seed germination temperature for most seeds is 78°F (25 C). When you expose your seeds to this temperature, they tend to germinate fast.

If the temperature is either too low or too high, your seed will take longer to germinate. When the temperature is too high, the heat stress will affect the seeds negatively. And the resulting plant will be too weak for transplanting after germination. 

Oxygen supports various physiological activities during germination such as respiration. An impermeable seed coat hinders oxygen penetration. This state is referred to as seed dormancy.

Light triggers seed germination while other seeds require darkness to germinate. 

Before a seed synthesizes, the embryo depends on the food material stored in the seed. After photosynthesis, the plant begins to make its own food. Auxins are the other growth-promoting mediums that are vital to seed germination.

Seed Germination Rate

Even with all the requirements, some seeds will not germinate. The rate of germination differs in various species. If seeds have been dormant for over a year after harvesting, they are likely to have a low germination rate.

>> Read our guide to fast sprouting seeds for kids to grow

However, this does not apply to all seeds. Others will still germinate after being dormant for some years. Like other natural things, seeds can be complicated times. You may provide all the right conditions and some seeds will still fail to germinate.

In most cases, plants that produce many seeds tend to have a low germination rate. Dandelions fall in this category. You’ll also find that those producing fewer seeds have an impressive germination rate. These are the likes of geranium.

Note that growing seeds in a heated propagator indoors will greatly speed up the germination rate.

So, How Long Does it Take for a Seed to Germinate

Typically, a seed will take about two weeks to germinate if it’s healthy and has all the germination requirements including the right temperature, moisture, and light. However, the soil temperature will heavily influence germination. The process will be faster if the temperature is about 78°F. 

“Seeds generally take 1-3 weeks to germinate depening on the variety and conditions”

However, other seeds can take up to 3 weeks to germinate. A good example of these includes rosemary and tomato seeds. If you want more accurate information on how long seeds may take to germinate, read the information on the packet.

What Slows Down Seed Germination?

When you plant seeds, you will expect them to germinate fast. But this might not happen due to several factors. For example, overwatering seeds can suffocate them. They will either fail to germinate or take a long time to sprout. The solution, in this case, is to stop watering for a while.

seedlings growing in propagator tray

Oxygen is vital for metabolism in seeds.  Before your seeds germinate, their energy emanates from aerobic respiration. When your seeds are struggling to get enough oxygen, they’ll either take time to sprout or fail to germinate. 

If you bury your seeds too deep in the soil, they will not get enough oxygen. Experts recommend a depth that’s at least 3 times the size of the seed. The instructions on the seed packet in regards to how deep you should plant them should guide you

Avoid planting the seeds too deep in the soil. Otherwise, they will struggle to break out of the surface. A big part of the stem will remain in the soil making your seedlings susceptible to damping off. 

The growth medium you choose for seeds may also influence their germination speed. Heavy soil may limit their oxygen supply. 

Damping-off is another problem that affects seed germination. It is a disease resulting from various pathogens. It causes the emerging seedlings to shrivel up and die.  If you are afraid that this may happen, avoid using garden soil. Use a soil mix that does not have a lot of wood chippings because they encourage the growth of fungi. Also, ensure that your planting tools are sterile. 

How to Speed Soil Germination?

After investing your time and resources in planting your seeds, you expect to germinate in due time. The problem is that sometimes germination may fail or take longer. Luckily, there are several ways to speed up seed germination.

Presoaking your seeds can help to draw in water and swell up. It also boosts the level of moisture in the seeds and triggers faster germination.  Also some seeds can germinate quickly using the paper towel method.

Other seeds have germination inhibitors. Soaking them for 24 hours or less helps to leach away these inhibitors. allowing the seeds to germinate.

You could also use stratification to speed up seed germinations. Seeds only grow when the environmental conditions are favourable. Stratification mimics these conditions. It means soaking the seeds, putting them in a bag, and placing them in a refrigerator.  This tricks them into “believing” that they are experiencing winter.

How fast your seeds germinate is dependent on a host of factors. If you’ve read this post, you now know what to expect when trying to germinate seeds. You can leverage this information to speed up your seed germination. And if the process drags on for months, your seeds are probably never going to germinate.

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