In this article, I’m going to discuss seeds harvesting, processing, and storage. Let’s get started.
To harvest seeds, they must be ripe and mature. Explained below are harvesting guidelines:
1) Your seeds should be collected from the best quality plants. Do not pick leaves or flowers from these plants as you are growing them for seed only.
2) Using organza, paper bags, or old stockings, cover seed heads and tie tightly to the stalk with string to protect the seeds from wind and predators.
3) With plant labels, identify each seed variety. A lot of seeds look quite similar.
4) Before harvesting seeds, they must be fully ripe. This deals with cutting off seed heads or the whole plant when almost ripe and drying undercover or perhaps, leaving to thoroughly dry on the plant before harvesting.
5) Seeds harvested before their prime will most times, grow if planted immediately. But take note, the seeds with the maximum time to store more nutrients last longest in storage.
6) Seeds or fruits containing seeds should be harvested around 10:00 am, after the dew has evaporated.
7) seed heads that require drying before the seed extraction treatment should be dried after collection so as to avoid mold or premature germination.
When it comes to seed harvesting, two types of crops are involved which are the dry seeded crops and the wet seeded crops.
1) DRY SEEDED CROPS
All of these crops are contained in dried pods, husks, or the seed-bearing portion of the plant. Certain seeds can be harvested before they are totally brown and dry if they are likely to be affected by pests and examples include; peas, corn, beans, lettuce, okra e.t.c.
However, plants in the mustard family e.g broccoli, kale, and cabbage will not continue ripening after they have been harvested. Thus, it is best to leave these seeds on the plant until they are fully mature and dry if possible.
Plants having seedpods that shatter such as lettuce, and members of the onion and carrot families are needed to be picked progressively as they ripen, most especially in wet or windy weather which can end up ruining or distributing the seeds. To extract seeds from dry seeded crops, dry processing techniques are employed.
Related: learn how to harvest petunias step by step
2) WET SEEDED CROPS
These seeds are from the Solanaceae plant family e.g tomatoes, eggplants, e.t.c and the Cucurbitaceae family e.g melons, cucumbers, e.t.c and they mature inside fleshy fruit.
To remove and dry these seeds, a variety of wet seed processing techniques are used. Fruiting crops which have seeds in their pulp e.g tomatoes and eggplants are best picked when the fruit is overripe, becoming soft.
Cucumber, zucchini, sweetcorn, and okra, are most times, picked young to eat but are needed to reach full mature size and left on the plant for another 3 weeks before the seeds get fully developed.
Capsicum and pumpkin are harvested when they are set for eating and are fully mature. The seeds for these crops are picked and scraped out of the cavity inside.
SEEDS PROCESSING & STORAGE
Seeds processing involves an improvement of the harvested seeds including many operations beginning from the harvesting of seed crop up to its marketing. The aims of seed processing include; an improvement of seed quality by the removal of adulterants, broken seeds, and non-seed material, to maintain seed viability and vigor, to make seed-handling easy, and to increase the real value of the seed.
The real value can be interpreted as purity (%) × Germination (%) 100. Drying of seeds helps to maintain seed viability and seed vigor for a longer period of time during storage. There are two types of drying which are:
I) Natural drying method: Here, seeds are uniformly spread at a clean place and dried under natural conditions.
II) Artificial Drying: Here, different artificial driers are employed and used to dry seeds. Examples include; box driers, bag driers, bin driers, e.t.c.
To clean the seeds involves separating physical impurities as well as removing non-seed material from seeds and we have two types which are wet cleaning and dry cleaning. Other seed processing activities include:
1) Seed Grading: Here, under-weight/undersized seeds are removed. Grading is done depending on length, width, thickness, and seed density.
2) Seed Treatment: This refers to the exposure of seeds to physical agents or certain chemicals which are able to protect them from pests and provide the seed with good health. The infected seeds may fail to germinate and may also introduce pathogens into new areas.
3) Seed Packaging: Bags of appropriate size and quality are used to pack seeds. The choice of packing material depends on the number of seeds, type of crop, and storage conditions.
We have three types of packaging materials which are; the Moisture-vapour resistance e.g polythene, the Moisture-vapour permeable e.g cloth, paper bags, and the Moisture-vapour proof, e.g tin cans.
Seed storage is known as the preservation of seeds under controlled environmental conditions which helps to prolong the viability of the seeds for a long period of time. We have the orthodox type storage and this type of storage includes small-seeded grain crops and vegetables and examples of Orthodox storage include long-term storage, medium-term storage, and short-term storage.
1) Long-term storage: They are provided mainly for the comprehensive base collection. Items stored are preserved for regenerating fresh seed and periodically examined for seed viability level. The purpose of this storage is for the perpetuation of the seed stocks. The life expectancy of the seed preserved will last from 30 – 50 years.
2) Medium-term storage: This type of storage is provided mainly for the seeds of actively used materials. The seeds stored will help supplement the base collection in long-term storage. Seed regeneration, as well as regular germination tests, are needed for materials in this type of storage in order to maintain their viability.
3) Short-term storage: Working materials that are used frequently or frequently requested, such as those with particular characteristics for research purposes, or those parents and progenies of the breeding materials are kept in this type of storage.
Read also: How To Harvest Seeds From Leafy Vegetables
I hope you find this article useful. I would like to hear from you. Let me know if you have any questions about seeds harvesting, storage, and processing.