Understanding plant seeds: F1 hybrids vs open-pollinated varieties

Most gardeners take huge satisfaction in raising fruit, vegetables, plants and flowers from seed. In the world of horticulture, two main types are often discussed: F1 hybrid seeds and open-pollinated seeds. To help you make a fully informed choice, we asked allotmenteer Rob Smith to explain the difference. Here’s what he said…

In the meantime, if you’re looking for new ideas to try, browse our full range of seeds for inspiration.

F1 hybrid seeds: precision and uniformity

F1 hybrid seeds are the result of controlled cross-pollination between two different parent plants that have been carefully selected for their desirable traits. This process, carried out by professional breeders, aims to produce offspring that exhibit a combination of the parents’ best characteristics. The resulting F1 hybrids are known for their superior vigour, uniformity, and often, enhanced resistance to diseases and pests.

The term ‘F1’ stands for ‘first filial generation’, indicating the first generation of plants produced from the parental cross. These seeds tend to produce plants that are more uniform in appearance and performance than those grown from open-pollinated seeds. They are specifically bred to improve yield, size, and sometimes, the plant’s ability to withstand shipping and handling, making them a popular choice for commercial growers and those seeking consistency in their garden.

However, F1 hybrid seeds have one notable drawback: they do not produce seeds that reliably “come true to type.” This means that, if you save seeds from an F1 hybrid plant, the next generation of plants will likely exhibit a wide range of characteristics, often not resembling the parent plant.

Open-pollinated seeds: diversity and sustainability

Open-pollinated (OP) seeds come from plants that are pollinated naturally, through wind, insects, birds, or other natural mechanisms. Unlike F1 hybrids, open-pollinated plants are more genetically diverse, providing a greater variation in traits such as size, colour and taste. This diversity can be beneficial, as it allows plants to adapt to local growing conditions and challenges over time.

One of the most significant advantages of open-pollinated seeds is that they “come true to type” when saved and replanted. This means gardeners can save seeds from their best plants each year, gradually developing varieties that are uniquely suited to their specific micro-environment. This is an excellent way to support biodiversity, resilience and sustainability in gardening and farming.

Open-pollinated varieties are often heirlooms, with seeds that have been passed down for generations. These varieties are cherished for their unique flavours, colours and histories, offering a special connection to the past and a counterpoint to the uniformity of commercial agriculture.

The choice is yours

Both F1 hybrid and open-pollinated seeds have their places in modern gardening and agriculture.

F1 hybrids offer consistency, vigour, and often, higher yields, making them suitable for gardeners and farmers who prioritise these traits. On the other hand, open-pollinated seeds offer genetic diversity, adaptability, and the opportunity for seed saving and sharing, appealing to those who value sustainability and heirloom varieties.

When choosing seeds from Thompson & Morgan, remember that F1 hybrid seeds are clearly labelled as such on each seed packet, while those not marked as ‘F1’ are typically open-pollinated. This should help you to make informed decisions and fill your seed tins with the appropriate varieties for your allotment or garden.

We hope Rob’s explanation has been helpful. If you’re looking for more information, our seed sowing guide covers everything from germination advice through to hardening off and planting out. We also publish a full list of exactly which seeds to sow now to make sure you make the most of every opportunity to get sowing!