Collecting seeds: Choose to grow open-pollinated varieties

SINGAPORE – Vegetables, fruit and flowering annual plants are popular among gardeners due to their rewarding nature. Many of these plants are raised from seeds that are bought from local nurseries. Gardeners often collect and save seeds from their plants so that they can grow and enjoy them again at a later date.

When buying seeds, make it a point to read the information on the seed packet, especially if you intend to collect and save seeds for future growing.

Pay attention to the variety – whether it is an open-pollinated (OP) one or a first filial generation hybrid, also known as F1. Most seed companies will indicate on their seed packets when a variety is an F1 hybrid, while those that are not marked as F1 are typically open-pollinated.

Depending on the needs of the grower, either F1 hybrid or OP seeds can be used. Both types of seeds and plants are not genetically modified.

Collect open-pollinated seeds

Seeds of OP varieties come from either natural cross-pollination of plants of similar cultivar or self-pollination of flowers found on a plant.

OP varieties are described as true to type as they will generally retain the characteristics of their parents and are genetically diverse. Seeds produced by OP varieties can be saved and replanted again.

Some of us may be familiar with heirloom varieties, which have been grown and passed down for several generations. These are OP varieties that are valued for various unique characteristics in a particular region.

When collecting seeds from OP plants, the gardener has to ensure that plants of different cultivars should not be grown nearby.

For instance, if two different brinjal varieties – one that produces purple, round-shaped fruits, while another has white, long cylindrical fruits – are grown in close proximity, pollinators can take pollen from the flower of one and deposit it into the flower of another. This will result in the creation of a hybrid.

In a small garden, you may need to step in to prevent the creation of hybrids between different varieties of the same plant species.

Besides ensuring distance between different plant varieties of the same species, which can be difficult to do in practice, another measure the gardener can undertake is to implement simple physical barriers.

This involves covering flower buds that are about to open with small bags to block access by pollinators. When the bagged flowers are observed to have opened, the gardener performs manual pollination that involves the deliberate transfer of pollen from a flower of one plant to a flower of another plant of the same variety. Manual pollination can be done via the use of a clean, fine paintbrush. The pollinated flower is then bagged again to prevent access by pollinators.

Another easy-to-implement measure to prevent the creation of hybrids is to organise planting times of different varieties of the same species in a staggered manner so that they do not bloom in the same period.

F1 hybrid plants likely not to resemble parents

F1 refers to the first generation of plants produced from the intentional cross-pollination between two specific inbred parent plants that have been selected for their desirable characteristics.

This tedious and complex breeding process is carried out by professional breeders and needs to be repeated for every batch of seed. As such, F1 hybrid seeds tend to be more costly.

F1 hybrid seeds will produce plants that possess little genetic variation but with desirable qualities, such as enhanced vigour, product uniformity, greater yield, larger size, better flavour and pest and disease resistance, which are needed by commercial growers. Commercially produced vegetables and fruits are likely produced by F1 hybrid plants.

F1 hybrid plants do not produce seeds that are true to type. The next generation of plants will likely be weaker and exhibit a wide range of characteristics that do not resemble those of the parent plant. Due to this reason, it will not be meaningful to collect and save seeds produced by F1 hybrid plants. You will need to buy new F1 hybrid seeds again if you want to regrow the same variety.