The plant population definition is similar to human population. It is the number of plants the farm can accommodate; through this, one will determine the number of seeds or sucker or other planting material to use for planting operation. The knowledge of determining the number of plants in a farm and number of seeds or planting material to use on a farm seems unknown to most farmers; people assume it is known to only professional farmers. This is quite correct because what you weren’t taught is obviously going to be unknown to you. But, if you are reading this article; knowing how to determine plant population or the number of plants on your farm becomes easy henceforth.

### This is how you determine plant population on your farm:

Plant population can be determined using several methods. But these three methods are commonly used. The first one is the use of plant population calculator; the other method is the study of plant population frequency by quadrat method and lastly, the use of plant population formula. These three methods can be used to determine the total number of plant on your farm.

Using plant population calculator is the easiest method. The calculator is an automated device or program that has been designed to determine the total number of plant that will cover a portion of land by the aid of data provided by the farmer. Such data are: land area, planting distance or spacing and seed rate. Once all these are provided, the device automatically provides the number of plants that will accommodate the provided land area. The use of plant population calculator is a pre-planting operation.

The study of plant population frequency using quadrat is also easy but does not provide accurate answer but an approximate answer as it a random based method. A quadrat, usually a square-shaped material with equal dimension and made of wooden material, is placed on certain portions of the farm at random. The plants found in the quadrat are counted and this process is repeated for 3 or more portions on the farm. The average of the result gotten in respect of the dimension of the quadrat is recorded and equated to the total land size to get the actual plant population of the whole farm. The study of plant population frequency using quadrat is a post-planting operation.

The use of plant population formula is the most effective and cheapest method. It is the manual method of the plant population calculator. It makes use of the same data as other methods. These parameters must be accurate to get accurate answers. The plant population formula is:

__Planting Area X Seed rate (Number of Seeds or Planting material per hole)__

**Spacing**

Multiply the Planting Area by the Seed rate and then, divide the product by the Spacing or Planting distance.

When the above is evaluated, the number of plants on the farmland or plant population is determined. Once this is achieved, it becomes easy to know the number of seeds or planting materials needed for the crop to be planted. Then you can estimate the cost of seeds and planting material yourself.

** For example:** To get maize plant population per hectare or tomato plant population per hectare, do the following.

Firstly, you need to know the area of your farmland. This area is not the total area of your farmland but the planting area; in other words, it is the space you intend to let your plants occupy, this is always determined through mapping out. Obviously, if you have a hectare of land; you cannot use 100% of the land for your planting; you will need some space for shade and other farm responsibilities. So determine the area you want your plants to occupy on the farmland, say 80-90% of the total farmland.

Another key parameter you need to aid your calculation is the spacing of your intended crop. Spacing is very important in crop production; spacing is the optimum feeding area or the most convenient area required by a particular plant to thrive well. Your crops need adequate space to garner all needed to facilitate their growth, such as: nutrient, air and water. Spacing varies with the type and nature of crops; the spacing for maize and tomato varies with the breed of the seeds and the seed rate, that is, number of seeds per hole.

For maize, 75cm by 25cm is used if one seed is to be planted per hole, 75cm by 50cm is used if two seeds are to be planted per hole and lastly, 75cm by 75cm is used if 3 seeds are to be planted per hole. Likewise tomato, the spacing varies from 60cm by 60cm or by 1m. So, determine the spacing you intend to adopt.

Lastly, you need to know the number of seeds you intend to plant per hole; this is called Seed rate. This depends on the viability and survival rate of the seeds. Some maize seeds are very viable and are planted just one per hole. Ideally, planting 2 seeds per hole is better and safe. Same applies to tomato, some tomato seeds are planted just one per hole, using nursery trays but in-situ, planting 2-3 seeds per hole is better. At times, you need to plant more than one seed per hole but later thin-out some seedlings as they grow to accommodate the most vigorous and healthy ones. With all these data determined, you can proceed to calculating the plant population or determining the number of seeds needed to adequately cultivate a specific planting area successfully using any of the aforementioned methods.

Maize planting population per hectare (10,000m) with a seed rate of one per hole, using the plant population formula, is approximately 53,333 plants. While tomato plant population per hectare (10,000m) using a spacing of 60cm by 60cm with two seeds per hole is approximately 55,556 plants. Try it yourself to see how simple and easy it is.

** NOTE:** The unit of calculation here is meters. Convert the centimeters (cm) to meters (m). For maize, the spacing becomes 0.75m by 0.25m and for tomato, the spacing is 0.60m.