The European Union (EU) returned Kenya to list of countries, which use high levels of pesticide in the horticultural produce, posing a threat to exports, the country's major source of foreign exchange.
The negative labelling comes just five months after Kenya was delisted in January, having partially complied with the requirements.
Blacklisting means that all the farm produce from Kenya must undergo mandatory time-consuming checks before they are allowed in the EU market.
"We have been listed having exceeded the required levels of residues,” says Ojepati Okesegere, chief executive of Fresh Producers Consortium of Kenya.
Kenya has over the years been fighting to be struck out of the list after it was first labelled in 2014.
Mr Okesegere says they were working with relevant government agencies to ensure compliance requirements adhere to the phytosanitary rules.
The EU had set a deadline of September 2014 for Kenya to cut the level of chemical residue in exports and comply with the bloc's guidelines, or risk sanctions on its cut flowers, fruit and vegetables.
The sanctions included closer inspection of Kenyan exports by the EU and saw some of the produce restricted at the market.
Measures the government took then included the banning the use of two chemicals, on farms, as well as increasing staff who ensured exporters complied with the rules, both on farms and at the point of exit.
Kenya Plant Health Inspectorate Service, a State agency tasked with ensuring the compliance levels on the produce, did not respond to our phone call by press time.
This comes at a time when Australia has also tightened rules on Kenya's export of flowers, with the new directive on zero pest tolerance.
The move has seen volumes of flowers sold to Australia drop after the stringent rule set by Australia took effect on September 1.
Australia had given Kenyan flowers up to last month to comply with zero pest tolerance on consignment of roses exported there, a move that has seen flower firms invest heavily on fumigation to meet the market requirement.
Flowers made the bulk of the earnings in 2018 bringing in Sh113 billion with fruits emerging second by raking in Sh27 billion followed by vegetables at Sh12 billion.