Often times you may hear folks say, “When landscaping always plant things in odd numbers”. There is a lot of truth to this. However, When dealing with plants there is a lot more gray area than black or white.
The first thing you need to know is whoever made that rule never said all the plants in that odd number had to be the same. For example you can plant two Spruce and three Pine and you have five plants. For you traditionalist that want to debate this and would say use five and three. In response I would say maybe you do not have the space for five and three. Furthermore, five and three equals eight which is an even number.
Obviously this design stuff can get foolish at times. Overanalyzing things is good to a point. I have overanalyzed things to great lengths where design is concerned. The thing I would say is once you know the rules you can break the rules. This does not mean just break the rules to be defiant. It is necessary to have some logic in place when you are doing design. Know why you are breaking the rules and be able to defend to yourself why its alright to use two Columbine with that one Dianthis.
There is a time and a place for even numbers in the garden. For instance if you are landscaping around a house with two pillars or other formal features like windows arranged the same on both sides of the front door. Go old school if you like. Old school meaning mirroring both sides of the house with the same plantings or some similar formal technique from 1974.
One of my former co designers told me a professor of hers at Purdue called the same two plants on the sides of the doors “guard plants”. I think this sums it up. They are like dobermans or marble lions. If they are Dwarf Alberta Spruce they almost have a vicious appearance about them.
Personally when I see a formal entry depending on the design I may use two of the same thing on both sides of the door. However, I then like to change the plantings the rest of the way out to the corners of the house or wherever the design ends. I think this approach is a little more contemporary and hip.
There is a certain part of the population that thinks this is a cluttery approach. If you are paying the mortgage its up to you to decide which side of the fence you sit on. If you are designing for someone else always try and please them. They walk in and out of the door each day and it is important that they enjoy what they see!
We couldn't be happier with the landscaping they designed and installed!