Samwise the Gardener

March in the Garden

March gives us thawing soil, spring cleanup, spring ephemerals and early warm spells that lure us out to see what’s sprouting and blooming. Hyacinths, forsynthia and hellebores start the show,…

March in the Garden

“It was one of those March days when the sun shines hot and the wind blows cold: when it is summer in the light, and winter in the shade.”
― Charles Dickens, Great Expectations

March gives us thawing soil, spring cleanup, spring ephemerals and early warm spells that lure us out to see what’s sprouting and blooming. Hyacinths, forsynthia and hellebores start the show, flowering beneath cold blue skies, heralding spring. But just when we think winter is over, a late snowfall can blanket our gardens and muffle our excitement, and we go back inside to plan some more.

Inside

When planning future plantings, the single most important thing you can do is make sure you have the right plant in the right location. Consider the mature size of the plant and its cultural (soil, water, sunlight) requirements, put plants in the conditions they will thrive, and group plants that like the same conditions together.

Seeding

March is the time to seed indoor most annuals and vegetables, usually in late March. Check out my February in the Garden post for more seeding tips!

Houseplants

Water houseplants that start sprouting new growth more frequently, and apply a weak fertilizer. You can make fertilizer from a surprising amount of things from your kitchen, such as crushed eggshells, banana peels, coffee grounds, green tea, molasses, epsom salts, and cooking water from pasta. Here are two good guides on making your own natural fertilizer, check out this article and this one as well for some guidance.

Outside

Days are warming enough from some plants to start sprouting. Keep snow piled up on beds or mulches topped up to protect plants from freezing nights. Try to keep off your lawn/garden when it is frozen, bare of snow and/or very wet to avoid damaging the grass or compacting the soil.

Spring cleanup and pruning

As snow melts, start cleaning up debris in your yard, such as leaves, sticks, garbage and dog poop. If you can, leave hollow stemmed debris for later cleanup, as a lot of beneficial insects over winter in the hollow stems.

Prune the D’s if you haven’t already-dead, diseased, dying, and damaged wood on trees and shrubs. After that you can make training and renovation cuts. Try not to remove more than 25% of a tree’s woody parts per year though! That can be too much of a stress for the plant and could lead to its decline. For more detailed pruning information, I would recommend The Ultimate Practical Guide to Pruning and Training book and this article from the University of Minnesota. Prune late-flowering shrubs (july or later) and perennials grown for colorful young growth.

Feeling overwhelmed by all the pruning work and things you need to know to do it? Contact me if you are local in Lansing, Michigan to talk about how I can help with pruning and garden maintenance.

Insect control

If your trees, shrubs, and vines have been struggling with overwintering insects and their eggs, such as scale, aphids, mealy bug, citrus leaf miner, mites and caterpillars, consider applying a horticultural oil (also called dormant oil or white oil). You can find organic options or make your own. There are two methods for dormant horticultural oil application. One is to apply it before the buds break or show any color. However, this can speed up spring bud development, making buds more susceptible to frost and cold temperature damage. The second method is the delayed dormant application. This occurs when buds are open at the tip showing 1/16-inch to ½-inch of green leaf tissue. Dormant oil should not be sprayed 48 hours before or after a freeze occurs or is predicted.

How to Make Horticultural Oil Spray for Organic Pest Control

Some plants are sensitive to dormant oil, you should avoid using it on these plants.

Plants sensitive to dormant oil*

  • Junipers
  • Cedars
  • Maples — particularly Japanese and red
  • Redbud
  • Smoke tree
  • Spruce — particularly dwarf Alberta

*Other plants may also be sensitive. Test a small portion of the infested plant prior to spraying the entire plant to determine if the plant is sensitive. Different plants exhibit sensitivity at different times of the year.

Early planting

As March heads into a close, we move into prime planting season for cold hardy perennials and bare roots plants. These establish more quickly when they are planted just as they are about to break dormancy, they are full of growth hormones and recover quickly from transplant shock. Make sure to call your utility companies at 811 before doing any digging, so you know where any buried wires, cables or pipes are to prevent injury and save time and money.

Some tips for planting your garden:

  • Don’t work with your soil when it is very wet or very dry.
  • Avoid planting in the hottest, sunniest part of the day. Overcast, cool days with little wind are the best, or plant early or late in the day.
  • Prepare your soil before you plant, to avoid damaging the roots later. Plants that need “well-drained soil” should especially get a good helping of compost and other organic matter amendments.
  • Harden plants off before planting. Annuals and perennials grown in a greenhouse have been protected from the cold, gradually expose them to longer periods of time outside so they don’t get shocked. Doing so gives your plants time to adapt to outdoor weather conditions and reduces the chance of transplant shock.
  • When planting trees or shrubs, only remove damaged branches at planting. Let them settle in for at least one year before you begin any formative pruning. They need all the branches and leaves they can get right now to get established in their new home!
  • Trees less than 5′ tall do not need staking unless they are in a very windy location. Unstaked trees develop stronger root systems.
  • Most plants are happiest when planted at the same depth they have been grown at.
  • Remove plastic containers before planting, they restrict root growth. With fiber pots, cut long the sides and remove the bottom to help the plant root more quickly.
  • Get your new plants in the ground as soon as possible. In plastic pots roots quickly get hot and dry out, so keep them in a shady spot until you plant them.
  • Water in plants well when your plant them, a longer watering but less frequent is better than more frequent but shorter watering. Long watering encourages stronger and deeper root growth.
  • Tuck your plants in well into the soil, press down on the soil around your plants when you transplant them–not too hard, not too soft. You don’t want too much air pockets around the roots for water and cold to flow into too easily, nor do you want it too compacted so that water can’t flow in easily.
  • Prior to watering your plants, check how wet they are by sticking a finger into the soil to the second knuckle of your finger. The surface of the soil may appear dry when the roots are moist.

Feeling overwhelmed by all the spring planting you need to do, or just want some help? Contact me if you are local in Lansing, Michigan to talk about how I can help with garden care and installation.