Japanese Morning Glory Care

It makes a difference what species your Japanese Morning Glories are as far as their care. The ipomoea nils a.k.a. Japanese morning glory large flower, for example, have different needs from the ipomoea purpurea or Grandpa Ott. Another common name for an ipomoea purpurea is Milky Way.

ipmoea nil and ipomea purpurea sepal differences
ipomea nil is on the left and the ipomoea purpurea is on the right

How to tell a i.nil (Japanese Morning Glory) from  a i.purpurea (Grandpa Ott or Hige)? The nil sepals are thin and pointy while the purpurea sepals are fatter and more compact.


 Ipomoea purpurea morning glories do not need any special care or attention except for the control of mites and aphids. Spraying and misting when it is time to water helps dislodge these tiny insects from under the leaves.

Ipomoea purpurea morning glories can be planted in almost any loamy garden soil as long as it has more to it than just clay. They are full sun plants so rich soil and not enough sun will result in lots of vines and no blooms.

Keep in mind that some varieties like double ipomoea purpurea morning glory Gypsy Bride are cool weather fall bloomers. Be patient if you are growing Gypsy Bride because this plant will amaze you by getting covered with blooms in late summer and early fall.

I prefer to grow other spring and summer blooming double types such as Sunrise Serenade and the Hige mixes because they don’t scatter as many seeds. The double ipomea purpureas are sometimes partially sterile so check the pollen and try tying some blooms and transferring pollen if necessary if you want to save seeds.

morning glory milky way
morning glory milky way

Japanese Morning Glory ipomoea nil care

Morning glories are full sun plants that require at least 8 hours or more of sunshine per day.  Afternoon shade can be beneficial during hot weather. Morning glories need enough water to keep the soil from becoming too dry. If the leaves droop during the summer, the plants may be conserving water. A soil test helps determine if the plants need to be watered. If moisture can be felt in the first one to two inches of soil it is best to wait another day before watering. Overwatering can kill morning glories by causing root rot.

Ipomoea nils are susceptible to getting rust infection under the leaves and it tends to spread by wind carried spores so lift the leaves with a wooden dowel and check them weekly. I plan to prevent rust by using the garlic soap spray and this also is useful as a bug killer/ repellent.

I have to spray for fungus and bugs often in my hot humid climate about every week and after it rains a lot. I spray in the evening to avoid burning the plants or disturbing the pollinators in my vegetable garden.

It is very important to spray underneath the leaves if you have aphids or mites. Lift the leaves with a wooden dowel and make sure the spray covers the underside of every leaf. If you only spray the tops of the leaves the bugs will hide and continue being pests after it dries. Go after those little varmints.

I have resorted to using Bonide Organic Garden Dust dust a few times when the bugs were getting terrible.

   Rust,Disease and Insect control for ipomoea nils:

Organic disease control is the best method for ipomoea nils because this helps with plant growth and seed production. If a morning glory becomes infected with rust under the leaves it will need to be removed, so the best treatment for rust is prevention. It is possible to try salvaging a valued cultivar by removing the bad leaves and spraying every other day for a week. It would be a good idea to continue keeping the infected plant separated from the healthy plants.

Overcrowding can make conditions favorable for diseases and too many plants to care for can make a preventive spraying schedule difficult to follow. Prune the leaves so air can circulate freely and reduce moisture under the leaves. Scout every square inch of the garden and surrounding areas frequently to make sure no disease is present.

Stay away from pine trees if possible. I found out I don’t get rust problems when I plant on the other side of my house away from the pine trees growing in the back yard. Pine trees are a rust vector. I have stopped planting under or near those trees and this past year or two I have no rust problems and that is while using my garlic, cayenne, and soap organic spray. Also, I have most of my vines finished and cleaned up before the fall when rust starts. My best prevention has been to plant after it gets warm in the spring and clean up most of the vines by the end of summer.

 Garlic,Cayenne,neem andSoap Spray (It really works if used weekly)

8 cloves of garlic chopped

1Tb Garden Safe neem oil extract

1 cup of water

1 Tb cayenne powder

1 Tb Dove dish soap

Let this soak overnight outside because it really stinks. Strain through cheesecloth into a gallon sprayer. Spray in the late evening covering all sides of plants and leaves once per week or after a rain. It does well in the veggie flower garden areas as well.

Dusky purple Large Flower Japanse Morning Glory
Dusky purple Large Flower Japanese Morning Glory