Noone knows, as yet, least of all the UK government, how Brexit is going to work out. We will continue to take orders from the UK on the optimistic basis that by September of 2020, when we would expect to deliver those orders, it will be possible to deliver irises to the UK. However, we will have to accept UK orders on the footing that it may be necessary to add an additional charge to cover the cost (once known) of a phytosanitary certificate and/or customs charges or taxes. We anticipate that we may be able to keep any additional costs to a minimum by importing all UK orders as one batch, sent to ourselves, and then despatching onward, which would enable us to divide any additional costs across all UK orders in order to keep them proportionate. When checking out on our website for an order to be delivered to the UK you can select the payment option "Payment for an order to be delivered to the UK", which allows you to defer payment until you know what you are in for. We will then notify you of the full costs once known and you can pay by bank transfer or paypal, or cancel your order if it turns out that additional charges make it uneconomic. If you choose to make a payment at checkout, we'll let you know prior to despatch if there is an additional amount to pay and you will have the option of cancelling the order and getting a full refund.
Should the position be clarified in time, such that this workaround is no longer necessary, so much the better. Fingers crossed!