Canes turn black? How Bonsai plant sealant can save your roses

I used to have the canes and branches of my roses turn black countless times; until I know the secret of plant sealant! If not for my husband who loves Bonsai, I wouldn’t know such a product.

I was asked again in the forum today about the plant sealant after I posted about it few months ago in the forum. So I guess it’s much better to write it here so others can access this information easily and I don’t have to search or write about this twice.

So, there are few tips that I want to share with you here today.

TIP 1: When you carry your deadheading (potong bunga tua) routine; ensure that the cut is angled properly (angular cut) so water won’t sit on the cut. The wound area is also minimized. And do cut it near the bud eye (mata tunas) on the canes as the plant can heal easily and quicker this way. You also, in a way, minimize its exposure to the fungi.

TIP 2: Only use sealant on big canes (but I recommend using sealant for small canes too under wet weather) but you can forget about using it on peduncles (the neck of flower / tangkai bunga) or any other smaller wounds. It’s a useless and baseless act. This is because younger canes usually have plenty of growth hormone that will indirectly inhibit the growth of fungi. In short, fungi don’t like growth. And this is also why you must deadhead near a bud eye – that is a growth.

So, what is a plant sealant?

It is a rubber or wax sealant applicable for any wound, graft or potting cut, in order to protect them against pathogenic fungi, bacteria infringed and to improve healing.

Left Photo 1: Stem that is protected by the sealant. I applied it months back. The remaining stem under the sealant is still green and healthy.

In plain words, the sealant will prevent the fungi from entering the wound and at the same time improves the healing process. 

Other names for it are plant wound dresser and grafting paint.

For canes that are already infected with canker, just cut the canes down to a healthy level and place the sealant on the cut.

How to use it?

• Cover the entire wound and the sides with it. 
• Make sure the wound is clean from sand and not wet before the application. 
• It is wise if you use a stick to apply as the sealant is sticky and may be difficult to wash off. But I often use my finger to apply; the sealant is made from rubber and I kind of enjoy this being grit and grime of gardening.

Above Left Photo 2: Stem that was not treated with sealant turn rot and the infection moved downward to the healthier part. Thanks to the branching stem (growth) on the left and the general health of the tree, the canker stopped where it is.

Can glue be a sealant?

I was asked this question by a forumer if she can use glue as sealant. Well, my answer is I don’t know. You got to try if you want to know.

• But what I know is that sealant is made specifically for wound dressing and that it helps to heal. Glue doesn’t. 
• Plant sealant is made from rubber therefore it is natural but glue is made from synthetic material. 
• The rubber does stick well on the plant and gives good seal. But I am not too sure if glue can hold up long and prevent fungi from creeping in though. 
• Overtime, glue may have adverse effects or even can be toxic to the plant. 

That’s my view.

Above Left Photo 3: What's left after sealant is applied  months ago. The stump after a while becomes dead, but the other main stem was saved from being infected. The tree is now 5 feet tall and flowering well. 

So, which product that I use?

The plant sealant that I use is “Spectra Care”. 

It’s meant for the Bonsai tree. It can be found at most nurseries. If ‘plant sealant’, ‘wound dresser’, ‘grafting wax’ fail you with the nursery attendant, just mention “Spectra Care” to him or her; and most likely he/she will lead you to a far corner of the store and point you to a dusty rack.