How to Determine the Correct Spacing of All Garden Plants

Controlling Algerian Ivy & Plants that Attract Birds

All nurseries will provide you with information when you purchase plants as to correct spacing of the plants you buy. Most plant labels have size and spacing listed on the label. Always ask the correct spacing of plants at purchase time. If you failed to do this, you can find information on spacing in paperback books on landscaping and ground covers, and on the internet. As a general rule, it is not an appropriate use of my time to be providing it since there are so many thousands of different plants that we grow here, and each have different spacing. Nonetheless, since you wrote to me, I will provide it this time, but I would like to help you find this sort of information for yourself. For example, if you had simply Googled “Correct spacing for Bougainvillea ‘La Jolla’ “you would instantly have gotten the information: 6 to 8 feet apart. Now it’s time to use your head. Ask yourself: “Am I going to plant in drifts for an all-over look? Or am I going to dot these plants on the hill with the ground cover between them?” These kinds of thoughts in your head will help you to come up with sensible answers: For example, you might decide to put the plants further apart—as much as 15 feet apart if other plants such as plumbago and lantana are going between them.

Here is an example for how to find out correct spacing of all garden plants. Look at the label of your plant. It may provide spacing. Most plant labels do. Or it may provide mature size. Or to find out the mature size, if the label fails to say, look up the eventual size of the plant up in Sunset Western Garden Book, a plant encyclopedia every gardener needs. (My book does a different job. My book tells you when to do what and how to do it.) Sunset is a complete encyclopedia, an alphabetical list of almost every garden plant we grow in the West. It provides correct spacing for many plants or when not providing spacing it provides mature size. My book does not try to replicate this, that would be senseless. My book belongs side-by-side with the Sunset Western Garden Book and the two books work together, Sunset naming and describing the plants, and mine telling you what to do when.)

(Also in Sunset, there are some informative pages in the back on basic information. Please read page 726 How to Plant Shrubs and page 691 How to Plant Groundcovers. Also look at the index on page 764 for other planting guidance that might help you.)

Now here’s how to use Sunset to find out correct spacing when it is not provided: In the latest edition of Sunset Western Garden Book on page 552 (the most recent edition), it describes the mature size of Plumbago auriculata as making a mound 6 feet tall and 8—10 feet wide. Plant the specimens so they are exactly the same size apart as the eventual mature size of the plant, that is 8 to 10 feet apart. This is fine also for ‘Royal Cape’ or ‘Imperial Blue’, whichever one you purchased. (You mentioned ‘Royal Robe’, but I think you said that by mistake. ‘Royal Robe’ is the name of the best Solanum rantonettii, another lovely plant but it is 6 to 8 feet tall and wide and looks best with more water, so not as good on this bank.)

Find the spacing for all your other plants in the same way as I have described above. The correct spacing for every ground cover should be provided on the plant label or provided by the nursery if you phone them, but for many 6 to 8 inches apart is about right. Some shrubby plants should be place 12 inches apart. It all depends on the mature size of whatever you are planting and the way a plant grows whether creeping or not. Take the mature width of the plant and you then have the correct spacing, or for a quick cover you can put them a little closer.

Yes, you can purchase lantana in flats and if you do, then plant them closer together. But the variety of lantana that is most frequently available in flats is a species called Lantana montevidensis, which is a purple, trailing lantana, not the same color as ‘Radiation’, which is a whole color scheme in one plant and is a more shrubby type. When planting lantana from small plants from a flat, put them closer together, —about one foot apart— than you would if planting from one-gallon or five- gallon size.

Regarding the ivy (probably Algerian ivy) it would be best to cut it off and keep it cut off and pulled out on your side of the fence. This is what I do in one part of my property where a old bank of ivy is separated by a flight of steps made of concrete sacks from the rest of the garden. We just keep policing and cutting it off and pulling it out and this way have successfully controlled it for many years. You can plant right over the ivy if you want, but unfortunately it will eventually climb up and cover over some of your plants, spoiling their appearance. It will, however, help hold the bank.

Yes, birds will be attracted to these plants, but you didn’t mention until now that attracting birds was a priority. Had you done so I would have suggested an entirely different group of plants. However, hummingbirds will visit the plumbago and lantana flowers. Butterflies will visit both of them, but for lists of plants especially attractive to birds (and other pages of plants attractive to butterflies, and many other specialized lists), please see the book I wrote called “The American Horticultural Society Southwest Smart Garden™ Regional Guide.” I wrote this book of lists to help gardeners such as you choose plants according to where you are going to plant them and how you will use them. Plants that are especially attractive to birds are listed, described, discussed, and pictured on pages 132, 133, 134, 135, 208, 209, 210, 211, 242, 243, 298, and 299. (Also see the list of all the lists contained in the book on page 82.) In my copy I have written the page numbers on every page, since many page numbers were omitted by the publisher, D.K. This is a beautifully designed book, but the publisher D.K. had the crazy idea that page numbers on every page would screw up their pretty design, so they would not listen to me when I told them there should be a page number on every page. Reference books need page numbers, and this is a reference book, not just a coffee table book.