April 2011 gardening checklist

April is often the month when gardens start showing signs of spring. Buds are swelling, blossoms begin to show and the earliest bulbs are showing color already. Here’s a quick checklist of things to keep track of.

1. The Anchorage area and most of the Northern Rockies have varying last average frost dates… from early May in low-lying and coastal areas to late June for some of the high elevation sites. Check with the local extension office to find an estimate for your specific area. Don’t put tender plants out until after that target date unless you plan to protect them each night.
2. It’s a fine time to direct-sow cool season crops that can take light freezes, however be prepared for protecting from frost if it promises to drop well below a “light” freeze.
3. Be sure to open windows and doors of your greenhouse on sunny days.
4. Plant up bulbs, perennials, small shrubs and annuals in containers. Tender ones can be installed later, or keep the entire assembly inside until it’s safe.
5. Make a window kitchen garden… herbs, salad greens and smaller veggies are great in trays that fit on your windowsill.
6. Be sure to keep the garden well-watered if the weather doesn’t cooperate. Irrigation timers can save a lot of headaches! Polymer crystals that absorb water quickly and then release it slowly over time are a boon to container plantings.
7. Create a pathway through your landscape. Use stepstones, woodchips, crushed gravel or other substrate to accomplish this goal. Lead the eye into your garden with gentle curves.
8. Spray or spread moss killer if you see significant competition from moss in your lawn.
9. Rake or thatch your lawn this time of year to allow oxygen to reach roots and fertilizer to penetrate better. Overseed immediately after raking/thatching if you have thin areas.
10. Mow LOW for the first time of the season. Scalping grass just as it breaks dormancy is a great way to thicken your lawn; grass stolons produce more blades in response.
11. It’s too late to transplant most shrubs and trees now. Wait until fall if you didn’t get to it. It’s a great time for planting berries for another month though.
12. Evergreens can be sheared for the first time of the season to encourage a tidy appearance through the year.
13. Prune your roses… hybrid teas to a few, short canes for larger blooms, but 5-7 canes if you want more abundant, but smaller blooms. Climbers and miniature roses should be pruned in accordance to their growing habits: side branches mostly for the former and minis require a lighter version of the method described above for hybrid teas.
14. Prune early-blooming shrubs after they fade from blossom and wait for later blooming varieties such as rhodies, lilacs, etc. until after their flowers fade. You don’t want to cut off this year or next year’s blooms.
15. Mulch this time of year to insulate tender new growth from some of the rigors of unpredictable weather, preserve moisture, and add nutrients.
16. Bait for slugs and snails now before they start laying eggs!
17. Spray organic Neem Oil as buds break on your trees and shrubs. Fruit trees especially are attractive to a host of pests, so carefully treat them with Earth-friendly controls.
18. It’s a great time of year to repot your houseplants if you haven’t done so in the past year. Watering container plants tends to accumulate minerals and salts over time, so fresh soil and cleaning the pot is a great way to start the season. Add compost to their soil while you’re at it. If they are root bound, either repot into a bigger size, or divide them before returning them to the same pot.
19. Plant perennials, biennials and hardy annuals as they arrive from garden catalog companies. New plants are usually shipped this time of year and they do much better if planted right away. Sweat them if they are bareroot and need help breaking dormancy. This is a process of rehydrating their roots for a few hours and holding them in warm temperatures for a couple of days so their buds swell and start to open.
20. Fertilize EVERYTHING this time of year! As plants come out of dormancy, they appreciate the nutrients of a balanced fertilizer. Whether roses, trees, shrubs, lawn or houseplants, they respond to the increasing daylength in spring with new growth. You can maximize that by providing them with nutrients.