Heirlooms and Hybrids

Have you noticed that the word 'heirloom' has become very popular on seed packets, in seed catalogues and on seed-company web sites?  But when can seeds be called 'heirloom' and why do seed-companies create the impression that heirloom is better than hybrid?

Agriculture in ancient times

We take the existence of agriculture and growing vegetables and fruit for granted, but once, a very long time ago, there was no agriculture and people hunted for and gathered their food.  Imagine what an incredible invention it must have been when mankind for the first time in history decided not to eat all the seeds they had gathered, but put some in the ground to see whether they could produce food right where they lived.

The first evidence of mankind growing food dates from around 10,000 - 9,000 BC. There is evidence of the cultivation of figs in the Jordan Valley around 9,300BC.  Squash was grown in Mexico in around 8,000BC.  Grain was produced in Syria at around 7,000BC.  During the same period rice and millet was grown in China.

The first evidence of the existence of farming communities dates from around 5,000BC.

The seeds mankind used were the result of a process now known as open-pollination. Open-pollination is the spontaneous mixing of genes of plants in nature. It maintains genetic diversity within the species.

Around 4,000BC in Egypt and the Americas people found out that if you did not just plant any seed you had, but saved seeds from plants that produced the best results and planted them the next year, the next crop was even better. 

This was the first time mankind began to influence the quality of seeds.  Mankind was now able to create better performing varieties by choosing some seeds and discarding others. 

Around 3,000BC Peruvians selected potatoes with the lowest levels of poison from around 160 wild species and began to grow them for food.

Skip just a few millennia to the year 1950AD (the middle of the last century) and using the techniques described above mankind had developed many varieties of thousands of food-plants.

What is 'heirloom'?

Seeds of open-pollinated varieties are now known as standard seed or heritage seed or heirloom seed.  

The term 'heirloom seed' has never been clearly defined, so anyone can call a seed 'heirloom', but in most cases a variety will be called 'heirloom' if it is an open-pollinated variety and was developed before 1951. 

 

Many heirloom varieties for sale today predate World War 2.  Many were real family heirlooms that a seed company obtained.  Some are hundreds of years old. 

There are also examples of newly developed heirloom varieties. There is a vibrant network of plant breeders who develop modern heirlooms. The Green Zebra tomato variety, for instance, was bred in 1983. Heirloom varieties are mainly used by home gardeners.

What does 'hybrid' mean?

In most parts of the world the widespread release onto the market of hybrid plants and seeds started in 1951.  This change was so profound for seed and plant breeders that few open-pollinated varieties have been developed since then.  Hybridisation of plants had been invented around 1720 in Europe, but only after the second World War methods were developed that allowed mass-production of hybrids that consistently delivered the goods.  

This is how you create a hybrid:

1. Select two parent plants that are closely-related relatives of the same botanical species.
2. Cut a male flower off one of the plants.
3. Rub the pollen on a female flower of the other plant.
4. Make sure this is the only pollination that takes place.
5. Wait for the fruit to mature and ripen.
6. Save the seeds.
7. Plant them: you have created your very own 'F1 hybrid'.

When you see F1 as part of a plant name it means the plant is a hybrid.

Whereas the hybridisation process sounds simple, most hybrids you buy are the result of hand-pollination by humans of very carefully chosen parent plants. 

Nature also accidentally creates hybrids at times.  Most of those fail. Some of them succeed, and lead to a new variety of plant.

Creating a hybrid is easy, but to create a hybrid that has major advantages over its parent plants and that can be reproduced reliably, so farmers or home gardeners get plants that are consistently successful, is not easy at all.  

It can take decades to develop a hybrid that the market is keen to buy.  Many attempts at hybridisation fail.  This is why it is understandable that a grower who develops a successful hybrid would want to patent it, so only they have the right to reproduce the hybrid.

Why did hybrids become such a success?

Here is an example of why farmers embraced hybrids: Asparagus producers are keen to grow male asparagus plants because they produce the thickest spears.  With non-hybrid asparagus varieties it takes three years before one knows which plants are male and which are female.  Hybrid varieties like 'Jersey Knight' were created specifically to be overwhelmingly male plants and to maximise crops for asparagus-farmers.

Successful hybrids can be a lifesaver for farmers, but there is another reason why nearly all breeders of new varieties switched to hybrids: hybrid plants are not true-to-type or true-to-seed.  If you plant seed produced by a hybrid the resulting plant will most likely not be like its parent. You may instead get a motley mix of poor performers that look nothing like the plant you took seeds from. 

If you want the advantages the hybrid offers, you have to keep buying the hybrid seed and that means that for plant and seed breeders developing hybrids is a much more lucrative investment than developing open-pollinated varieties.

Heirloom and hybrid compared

Let's compare the various aspects of heirloom and hybrid varieties:

• Yield: scientists found out very early that the simple act of crossing different varieties to make a hybrid resulted in plants that achieved higher yields. They called this phenomenon hybrid-vigour.  In many cases hybrids are more productive than heirlooms because of hybrid-vigour or because they were created for the specific purpose to produce more. Hybrids have made a major contribution to increased food production.  Corn is a good example: 

Parent1, F1 Hybrid and Parent2 in the field and on the right their corncobs

• Cost: heirloom seed is often cheaper than hybrid seed because hybrid-producers need to recoup their considerable development costs.  On top of that, to have the advantage the hybrid offers, you have to continue to buy the hybrid seed. If you buy a heirloom, you can collect the seed it produces and use that next time, at no cost.

• Diversity within one type of vegetable: over time nature and people around the world created many weird and wonderful varieties of many vegetables, sometimes using local wild varieties.  These are today's heirloom varieties. If you want to grow yellow carrots or a pear-shaped tomatoes or deliciously sweet tasting pumpkins chances are you will end up with a heirloom, not a hybrid, because the vast majority of hybrids were developed for 'industrial reasons' (shelf-life, mechanised harvesting, cool-store storage, tough skin that copes with transportation and so on) and not taste or unusual shape.

• Cropping period: let's say you buy ten hybrid broccoli plants because the heads they form are really superior in size.  These plants will be much more uniform than ten heirloom broccoli plants.  If you could examine their genes you would find that their genes are much more the same.  Be not surprised if they are all ready for harvest at around the same time. This is great for farmers because a whole crop can be harvested in one go and that saves money. If you prefer a gradual harvest rather than a glut, heirloom plants may suit you better. If you prefer to pick all your tomatoes at the same time to make tomato sauce, grow hybrids.

• Flavour: fans of heirlooms and seed companies catering for home-gardeners often claim that heirlooms taste better.  Taste is hard to measure and there is little scientific evidence of heirlooms tasting better.  ABC Gardening Australia (Sept 2003) explained that heirloom varieties were first and foremost created for flavour, but surely people in past generations would have tried to create climate resilient varieties just as today's breeders do.  The jury is out on this one.

• Biodiversity: today around 99% of US corn is hybrid corn (could not find an Australian figure, but it would be similar). The story is similar for wheat, soybeans, cotton, peanuts, and many other crops. The genetic diversity of many major food crops is now very narrow and that is risky because a pest could wipe out entire crops.  
  Before the industrialisation of agriculture a much wider variety of plant foods were grown and that meant that the risk of a disease or pest wiping out an entire harvest were much lower.  
  Some wild varieties from which our present day food crops came have gone extinct. Mankind has also lost many old varieties of vegetables because they are simply not grown anymore.  
  There is now a strong movement to locate wild and old varieties and keep them alive because mankind will need them when creating new varieties in the future.  Home-gardeners around the world can play a big role in this by growing wild, rare and heirloom varieties.

• Ownership: This is a political issue and one that is important for home gardeners.  Heirloom varieties are not owned by anyone. If everyone around the world switched to hybrids and heirloom plants and seeds were not grown anymore, seed companies and governments would gradually own and control all seed distribution.
  

My conclusion

Some people see heirlooms as 'good' and hybrids as 'bad'. The reality is that both are needed.

With the world population growing rapidly, there is definitely a place for F1 hybrids because they reliably produce more food than heirlooms.  For home gardeners who want a big crop of reliable quality that is ripe all around the same time, hybrids are also a good choice. 

Most home gardeners grow their own produce for the taste and variety that heirloom varieties can give. Add to that the ability to collect seed and grow great produce at no cost, and heirloom is the choice for most home gardeners. Maintaining biodiversity is also really important and home gardeners play an important role in harvesting and maintaining viability of thousands of heirloom varieties.

Happy gardening!