Best practices in farming vegetables

My name is Mathew Mugenya. I am a fan of your weekly articles. I used to live and work in the city but Covid – 19 forced me to relocate and start a new life at my rural home. I want to venture into horticulture, starting with vegetables (sukuma wiki, spinach and cowpea) then progress to other crops gradually. I am, therefore, seeking your advice and guidance on the following: 

Which variety of sukuma wiki and spinach has broad leaves for better yields and grows fast?
Sukuma wiki, Thousand headed, Collards and Malkia do well. For spinach, Fordhook Giant will give you the best yield. The variety will depend on the ecological zone. 
Visit the nearest agrovet shop and they will tell you the variety suited for your area.

My farm has red soil, which variety of the above crops are suitable for that type? All these vegetables can do well in that soil. With red soil, which fertilisers are suitable for planting and top-dressing?
For planting, phosphorous fertiliser – DAP – is used while for top-dressing, CAN is commonly applied.
From which seed company should I buy the seeds to avoid fake ones?

There are many seed companies, buy seeds from a registered agrovet.
From which company should I buy pesticides to avoid counterfeits? 

There are many companies which manufacture pesticides and I don’t think there are counterfeit products as long as you buy them from a reputable agrovet.

Do I apply manure or fertiliser on the seedbed when planting seeds?
If you decide to apply manure, you should do it long before you transplant the seedlings to the seedbed (farm) and mix it thoroughly with the soil.

How do I plant seeds on the seedbed, in rows or randomly?
Plant seedlings in rows on the seedbed because each of the vegetable crops you have mentioned has its own spacing.

At what stage do I spray pesticides on the seedbed and which ones should I use?
You don’t just spray pesticides on your vegetables unless you have observed the presence of a pest. Different pests are sprayed using different pesticides. Therefore, the chemical will vary depending on the pest.

After how long should I transplant the seedlings from the seedbed to the farm?
Spinach and sukuma wiki seedlings are normally transplanted from the nursery bed after three to four weeks, and then planted on the seedbed (farm). For cowpeas, you plant directly in the seedbed.

What is the spacing between the crops?
The spacing for sukuma wiki and spinach is 45-60cm between rows and 30-40cm between plants or you can use a square spacing of 30×30cm. Cowpea spacing is 30-40cm between rows and 20-30cm between plants.

After transplanting, when do I apply top dressing fertiliser and weed? 
During transplanting, apply DAP fertiliser and top-dress with CAN four weeks after transplanting. Keep the field weed-free throughout the growing period.

Are the crops watered every day, or at what intervals?
After transplanting, you have to water the vegetables regularly until they take off. 
Thereafter, watering should be done when necessary if it is not raining, but you should practice regular irrigation.

When do I start harvesting?
Sukuma wiki and spinach harvesting starts 42-60 days after transplanting and continues for up to 1-2 years.

Harvest single leaves from below and avoid harvesting too many leaves from one plant because this will reduce the photosynthetic surface. Cowpea leaf harvest-ing starts 2-3 weeks after planting.

What is the interval between harvest periods?
You can harvest at weekly or fortnightly, but this will depend on whether you have leaves to harvest.
After spraying pesticide, how many days do I take to do the next harvesting?

The pre-harvest interval for the pesticide is normally indicated on the pesticide container and should be followed to the letter.

For how long do I harvest then uproot the crops for new planting?
For sukuma wiki and spinach, you can harvest for one to two years as indicated above, while cowpea leaf harvesting time is limited because it starts to produce pods for seed production. 
Remember for cowpea, you can also plant then uproot the entire plant, tie in bunches and sell.

What is your advice and recommendation on the use of foliar fertiliser?

Foliar fertilisers are applied on the leaves to supply micronutrients to avoid deficiencies.
What crops do you recommend for crop rotation?
Crop rotation is the practice of growing different crops or crops which belong to different families on the same piece of land in an orderly sequence.

This is made possible by dividing the land into plots and on them different plants are grown in a particular season. In the next sea-son, these crops are rotated or grown in the next plot.

Crop rotation is only possible in annual crops (crops which take a year or less to mature). Rotate with crops that do not belong to the same family because they share the same pests and diseases.
You can rotate with beans, sweet potato and pumpkin.    

Answered by Carol Mutua