Fall Feeding

It hardly seems fair, but November 1st is only a few weeks away, and we all know what that means–surprise cold spells that can take their toll on our gardens! Now is the time to begin a fall fertilization program to toughen up softer plants, but it’s also the time to step back from feeding indoor plants and tropicals.

Roses, azaleas, rhododendrons, camellias, fast-growing conifers, and heathers should be fed now with a winterizing fertilizer that has a formulation lower in nitrogen and higher in phosphorus and potash. Potash has a unique ability to slow down plant growth, shorten the internode stretch between branches, and toughen up plants. Our ‘go to’ in this case is 10-15-19, but for rhodos, azaleas, and camellias, rhododendron and azalea food is great. Summer flowering shrubs that have now finished blooming would appreciate an application of 10-15-19 as well. Remember to feed around the dripline of trees and shrubs for the best absorption into the root system. 

After a dry summer, many evergreens and conifers are in a stressed situation, and a winterizing fertilizer will tone them up before fall and winter. Don’t be surprised to see a good deal of needle drop as your trees clean out their inside foliage which has dried up because of a lack of water. This will happen in spite of any fertilizer you apply now. Fertilizing with Fabulawn 24-4-16 (yes, it’s a lawn fertilizer!) will, however, revitalize the colour of the tree and strengthen it for winter.  

Freshening up your planters for autumn? Awesome! 14-14-14 is a slow-release fertilizer that we recommend throughout the year for hanging baskets and planters. If you are updating your look with annuals, perennials, and even dwarf trees or shrubs, apply a top dressing of this around your planter to help them stay well-fed over the next few weeks while they’re still busy growing. They will ‘pause’ growing over winter, then perk up when the days warm up again in the new year. 

On the West Coast, lawns present quite a different situation at this time of year. The popular belief that they require plenty of potash for fall is not true. Lawns need nitrogen in spring, summer, and especially in fall. They require a controlled-release nitrogen fertilizer which will allow a small percentage of nitrogen to be released immediately and the balance over a three-to-four month period (during cold weather, the release rate is slowed down even more). The nitrogen released now will help feed and colour up your lawn after a dry summer. It will also strengthen many weak grasses and help to prepare them for cold weather. 

As the weather becomes cooler, your grass will simply stop growing, but the nitrogen will be stored in the cells of each grass blade, ready for use next spring. Try Scotts Turf Builder Fall Lawn Food 32-0-10.

One of the main reasons moss thrives in our lawns/soils is the lack of fertility, especially over winter. An application now of nitrogen will slow down moss growth. In a few weeks’ time, i.e. in November, apply Dolopril lime to your lawn. Lime helps keep soil pH balanced over winter, which is not only good for your lawn, it also makes moss less inclined to take hold (moss likes acidic soil, but lime will help keep it neutral). If you can get it done now, aerate your lawn and rake in ¼” of sand. This will help improve drainage and deter moss.

Fall and winter vegetables could use some nutrients too. Feed root crops, brassicas, and leafy veggies with 10-15-19 to give them a bit of a boost before they start to slow down for the season.

Indoor plants will soon be going into a semi-dormant state. Feed your houseplants one last time in September with 20-20-20 (Marphyll, a marine phytoplankton feed, is a good organic alternative), but after that, you can take feeding off your to-do list until late March, when the days lengthen and plants start actively growing again.

Folks with Christmas cactus that are nearing ‘bloom time’ are reminded to keep their plants at about 10-12C right now to initiate bud set. Temperature, not feeding, is what will help them now. 

After a year of stress on your garden, taking the time to feed your plants now, before the cooler weather sets in, will help give them the boost they need to make it through the next few months, and to be in a strong growth position for next spring.